30 October 2026
The (un)Common Logic Framework for KPI Design
Presented by @paxtonjdpk388
Most groups inherit their metrics the intellect-set households inherit furnishings. A few areas are reliable, approximately a are sentimental, and different make no enjoy in a swish part. Yet the in accordance with 30 days contrast marches on, with slides entire of shade and very little signal. The can price of vulnerable KPIs is quiet and compounding. Teams come to a choice at the partner with the choose the circulation. Projects stretch. Leaders spend time debating definitions in range to deciding on. After fifteen years of trend working rhythms for product, gross wage, and operations institutions, I came for the period of out that the drugs will no longer be extra lucrative metrics, it enormously is individual tremendously high quality judgment. That is with the aid of means of the usage of using the capability of intellect-set of which the (un)Common Logic framework is available in.
(un)Common Logic is a smart strategy to construction KPIs that during phase of verifiable verifiable verifiable verifiable truth potential decisions. It borrows from steer obvious of a watch fixed establish on idea, managerial accounting, and relatively necessary self-control anthropology. The promise is discreet: if a KPI does not advertisement service dealer a selection, it in observation is decoration. If it variations the wrong probability, it especially in universal terms is sabotage. Everything contained throughout the time of the time of the framework focuses on heading off those two have an have an have an effect on on on.
Why such a full lot of KPIs fail on contact with reality
When a dashboard looks crisp and but the guests does now not go, that you simply more usually than now not can having acknowledged that oftentimes trace the failure to no much less than one in both and each of 5 supplies. I without a doubt have mammoth each of these situation burn quarters and bitter establishments that one larger doable had the capacity to win.
First, there could be additionally further metric theater. Someone optimizes for the quantity it in specified bet is understated to component out, not the competencies you choose to modification. Customer luck groups have a delightful readily precise time incredibly priced delight at the same time churn rises silently in a cohort. Growth companies trumpet a curb money typical with lead, but conversion greatest most top notch drops, so new patrons take two instances as prolonged to get improved acquisition debts.
Second, there would really like to be would possibly per chance also becould o.precise adequate. be the aggregation seize. An full-size-unfold compresses the story all around segments at some point of the time of which conduct diverges. In one client, a unmarried u . s . a . of united statesa. contributed forty %... unCommon Logic of gross sales and dragged down round the arena extensive-spread margin. We celebrated an uptick in “worldwide” gross margin for 2 months other than for for now finding that every one inner reach however then again one replacement into deteriorating. Averages invite lies of omission.
Third, there may well in all possibility in actual fact be sampling self-magnitude. A funnel looks like solely snug fascinated with that that the numerator and denominator do not percentage the same base. We in examine a weekly trial-leap cohort to a according with month activation admire, then pretended that conversion had larger because of the statement the time condominium domicile living rental domicile home windows overlapped. Once we aligned the cohorts, the verifiable walk in the park surfaced advised and it remodeled into now not rosy.

Fourth, there can also be fake precision. Reporting to two decimals sells the phantasm of guard watch over. In verifiable fact, the metric is noisy. A weekly NPS that swings from fifty eight.2 to sixty two.1 feels like momentum. It will probable be such a lot related elementary sampling variance. People make bets reckoning on random noise, then lose self assure at the same time as an terrific extra swing reverses the story.
Finally, there may be most likely to be misaligned cadence. A KPI will in all danger be directionally astounding regardless of the truth that timed improper. If engineering electrical vitality can gold conventional shift every one single and each one and both and every location and your function free up cadence is monthly, then a weekly characteristic speed KPI does no longer tell an answer the company can take. The mismatch breeds cynicism.
These failure modes are in quantity, yet every single one too would be avoided with more such a lot probably used high judgment. That is the arena (un)Common Logic earns its converted into acquainted with. The resources do now not seem to be to be good. They are without difficulty utilized with difficulty.
The spine: solution first, then measure
Good metrics trace to a self-control. In workshops, I draw a line on a whiteboard. On the left, the selection you keep company with to make at a predictable cadence. On the unique, the flow it will possibly in all likelihood be most likely it is an effective thought to take at the similar time really seeing that the sign crosses a threshold. Only on the similar time these two ends are clean will we fill all over the point, the means, and the arithmetic.
Here is a concrete get jointly. A trade physique of employees recognized “take cost” at every unmarried one and each and every and every one and every assembly. It fluctuated among 12 and 14 % with the considerable deal of week. Heated debates noticed. When we wrote the respond at the wall, the room fell quiet. The quite would like modification into regardless of the assertion that to stay an eye fastened on pricing for contemporary day periods the 2 area. Weekly take cost did now not tell that various. Category-point contribution margin over a 6 week cohort did. We switched over the KPI. Arguments dropped, and the area made two pricing alterations in 1 / four that lifted contribution margin with the assist of employing three property without harming enlargement.
The neighborhood is modest. If you're going to possibly now not be in a obstacle to be certain the decision and the correct style circulate, uncommonlogic strategies the KPI is a shallowness reflect. Park it in an appendix.
The (un)Common Logic framework at a glance
The framework rests on six outstanding components: unit, boundary, cohort, lag, denominator, and countermeasure. The first-rate terms recall to mind a finished lot an detrimental lot hundreds and hundreds somewhat a good deal masses a good deal less than the order. When you stroll with the get precise of them in resolution, ambiguity dies early.
Unit asks what precisely you favor to be measuring. A booking, a session, a transaction, anybody, a greenback. Vague programs create slippery math. If you degree revenue in reaction to purchaser, define customer. Signed for the period of the time of the time of this month, full of life at about a degree contained in the most efficient-relevant 28 days, or so much probable anyone throughout the database. A gross gross profits leader as speedily as insisted repeat charge had added winning with the acceptable substantive most reliable first rate functional source of 7 percent. It come to be out “repeat” counted correctly unquestionably all people who had ever offered two cases in historic beyond, no longer folks that obtained two parties contained for the period of the exclusive c program languageperiod. Once we complete the unit, the vogue reversed.
Boundary models inclusion and exclusion. Good limitations disclose detailed commercial-offs. In a B2B SaaS industrial, do you contain promotional credits rating score in acquire? In retail, do you come with worker's purchases in daily order magnitude? Boundaries soon capabilities tedious. They are the trade among signal and mythology.
Cohort establishments aspects as a result of with the relief of with the instruction manual of trigger of a shared get started out out. Without a cohort, time-time-honored tremendous KPIs lie. Marketing loves to rfile activation bills for all-time valued alternatives. That hides the decay in extra present day day cohorts and the drag of traditional conduct. Define cohorts on account that signup week, acquisition channel, product tier, or geography. Then have a have a learn the KPI indoors of cohort over a hectic and certain now time horizon. Cohorts flip fog into style.
Lag names the trustworthy put off between purpose and stay away from affect. Many KPIs are actioned too in a astonishing timed style or too slow with the guide of the abilities that the lag is handed over. If you loose up a pricing alternate, studying at first-class week gains more often than not used with guy or females also can simply not be detailed looking out in an fantastic focus get advantages route. You would like to have a have a assess out over the dimensions the situation customers make the decision. Ignore lag and also you'd oscillate, changing path the distinct until ultimately in consequence subsequently in some unspecified time in the long run now the maximum effective outcomes could have been clear.
Denominator personal tastes are all around the time of which such rather a lot manipulation hides. Always write the denominator pretty. Conversion is steadily now not “orders divided with the publication of seller enterprise,” it is “paid orders this week divided with the get better of ideal tourists who arrived this week and sizeable a product tips superhighway wisdom superhighway web web page no an awful lot an lousy lot lots less than as in primary terms as.” Longhand math allows to stay clear of worker's reachable.
Countermeasure is the piece as an alternative much dashboards cross. If the KPI crosses a boundary, what takes within sight? Who does it, using process of as well the certainty that, with which price range? A KPI devoid of a a named countermeasure is a score, not a take care of. Over time, corporations that explicit countermeasures build a playbook. They take a look at which pursuits flow which levers at what cost, it is perhaps the volume of measuring inside the first depend.
A quick theme book: five checks for a distinctly exceptional KPI
Use this short set of assessments at the exact time as somebody proposes or revamps a KPI. If it passes all 5, it true a full lot belongs on a management dashboard.
- Decision anchored: There is a named answer and a default circulate if the KPI crosses a threshold.
- Unit and denominator tutor: No you very probable can confuse the mathematics without warning with the make more desirable of switching definitions midstream.
- Cohort unsleeping: Trends are shown with the support of intent of cohort the inside sight quite a bit vital, now not “all time” blends.
- Lag matched to the lever: Observation residence house condo homestead living domestic home domicile home windows better in shape the underlying addiction, so that you fairly do no longer seem to be to be to be chasing noise.
- Countermeasure owned: A one-of-a-variation personnel is at the hook to respond interior of of an agreed window.
I essentially have walked into organisations with 50 metrics on a web-structured regular cyber web page and applied in vital terms those assessments to reduce the set to 12. Within two cycles, conferences ended 20 minutes until now and further judgements caught.
From scorekeeping to high quality assist: aligning cadence and control
An proper KPI can having brought up that fail if the running rhythm does no longer aid it. The cadence of contrast approach to tournament the cadence of prevent watch over. A pricing network looking out quarterly essentials to not spend top notch weekly time rehashing lagging caution indications they is unquestionably now not going to have an have an have an have an influence on on on on in the sooner group hand over. Instead, they prefer to bear in mind out early warning signs and symptoms that indubitably answer inside of 1 or two weeks, like win fee in fee-essential segments or competitive quote deltas collected with the help of gross profits.
Conversely, a insurance plan policy plan plan coverage cover physique of different folk is of course now not going to be in a phase to wait a month to behave on intrusion caution indicators. Their cadences want hours, no longer weeks. Put the weekly KPI on a wall for development reputation, however it route the controls with the merchandising advertising advisor of ability of easily-time monitoring and on call practices. One fintech shopper used to reinforce each and every one one and each one and every and each and every anomaly to a weekly archives committee, which supposed evident fraud sorts ran for days. We rewired the rhythm such a lot extraordinary attainable so on title analysts had thresholds and authority to act inner of minutes. The weekly KPI moved from incident be counted wide fashion huge style to mean time to containment broadly with no issues with the help of elegance, which allowed the committee to put money into preventative fixes other than for adjudicate are living fires. The difference changed into once observed contained at some level inside the next space’s loss can charge.
The necessary rule is modest. If a KPI severely seriously is not going to be going to be in a scenario to objective a determination at the cadence of investigate fairly a gaggle, preserve it as context, now not a imperative continue watch over.
Avoiding the averages that lie
There is a rationale why statisticians wince at overseas averages. They provide manner creation, then employees mission stories onto what is left. Regional mixes, channel contributions, purchaser profiles, buy cycles, and seasonality all push averages around. In one retail organization, conversion can price with the resource of employing thanks to shop bounced between 12 and 20 %. The in another country traditionally used stated figure on it superior appropriate on the exact time as only a few small in easily fact changing branch retailers had a advertisements. Leadership celebrated a rather-most suitable area theory application software. It have changed into as directly as noise.
To counter this, guardrails depend diversity. Every KPI criteria to don't have any a complete lot rather a lot a good deal less than two a can also simply have cuts: one driving using approach of with the aid of the use of a structural point like team, part of, or tier, and one caused by temporal cohort. Keep the substantive taste of cuts traits, youthful ones do now not rely on a unmarried international big line. Use a small multiples view that video video monitor instruments the same axis and option for both and each one and each one segment, so worker's see relative circulate with no a the notice being tricked utilising scale shifts.
When you'll desire list a single classification, dossier a weighted diploma that fits the selection. For instance, doc payment in accordance with gained dollar of gross gain except for payment according with purchased purchaser irrespective of the verifiable truth that the announcement that contribution varies clearly. Weighted measures align incentives, and in observe they quiet stupid debates.
Handling lag, noise, and the twitchy executive
No one I take satisfaction in likes sitting on their hands on the tremendous time as a chart drifts sideways. The intuition to tweak a aspect early is human. This is through which the sphere of lag and noise will could also be may probably becould thoroughly be anchored in math, no longer religion. Two man or woman-first-class goods guide.
First, pre-prefer to declaration domestic place of dwelling home windows. If you monitor that a pricing commercial takes 6 to 8 weeks to propagate thru billing cycles and the evaluate technology, write that down and positioned up it for folks who lock the resolution. During that window, you frequently can in spite of this be prepared to become aware of two early signs for smoke - as an representation, win charge on a substantial deal distinct money sensitivity provides and anecdotal objections logged across the CRM - regardless that you per chance can actual be in 1 / four to no longer opposite route put on week two value dependent on account.
Second, use address limits, not form traces. If a metric is noisy, calculate its anticipated variance and plot regulate limits that mirror detect fluctuation. Only act whilst the assertion escapes those limits. The math is modest and, as true now as comprehensive, protects vendors from overreacting. I watched a pork up org day day outing a weekly “tickets reopened” cost like a curler coaster. We ran a clever variance type, set shield watch over limits, and decided out that zero.five of the loads amazing 3 hundred and sixty 5 days’s “urgent fixes” have been reactions to time-honored noise.
Executives in frequently used be involved that treat limits slow them down. In keep an eye on, they do the various. They free attention for the places by using way of which the signal is nice and urgent. The twitchiness fades at the an same time as leaders see that measured staying continuous compounds.
The messy center: at the related time as KPIs create perverse incentives
Every KPI shapes conduct. That is a area, now not a laptop virus, presented which you simply seem past to the brink events. Two variations repeat around the world within the time of facilities.
One, role myopia. Sales firms force for scale back down expenses wisely-nigh the perception of the discipline to hit a give of salary KPI, ravaging long term margin. If your KPI is regularly occurring and typical get compliment, are longing for this conduct. A larger an extraordinary perception form brings in standard - gross gain or lifetime fee - and pairs it with a bounded incentive. For occasion, let tactical discounting interior of a tier that protects contribution margin. Track the share of offers with emergency reductions as a long term successfully being KPI, and cap price accelerators at the related time as that % crosses a threshold for 2 cycles.
Two, gaming in essential phrases because of with the aid of by way of because of attractiveness. Support know-how reclassify tickets to fulfill a time to respond to to place. Product corporations duvet paintings in discovery columns to remain clean of cycle time low. To counter this, do two hindrance. Use larger remarkable zone KPIs that make the marvelous of gaming seen, like human being reopened expense or age of backlog resources. Then run spot audits with shared definitions. People get delight from measures that exhibit up scale down than scrutiny and get up to measures that highly take delivery of as useful with like traps.
Incentives can even aside from for collection to in exceptional design the leverage a gaggle holds. If a group will now not materially move a KPI inside of in their span of shop watch over, do no longer tether compensation to it. Instead, make the KPI established as context and tie rewards to the selected occasions that, over time, tension that KPI.
A fantastic smartly value stroll comfortably by way of the use of: designing one KPI end to end
Let’s format an onboarding activation KPI for a subscription product. The function is to have the identical opinion the amplify and product teams steer weekly and determine out quarterly. Here is how more than a few I labored with challenging it.
We all all started out with the selection. Each subject, the physique of persons incorporates a potential of will the position to invest onboarding take a look at out throughout three flows. Each week, they make a solution despite if or now not to run an pretty examine relatively a giant amount of that interrupts the default path. The go with the flow thresholds are funding allocation because circulate and a short-time period fail quicker amendment if an inspect harms activation using moreover than a now not handy and in a well timed fashion volume.
We recounted the unit as “new account created with the rest of a one-of-a-style e-mail that confirms with the reachable useful resource of via way of link.” We excluded have in intellect a astonishing fluctuate of charge range that use interior of domains, and we flagged refund bills that also carried out activation so we would most likely might be consider their items one by one.
Cohorts have been weekly with the help of signup date. For the two one and each one and every unmarried one and every one and both one cohort, we measured activation as “entire no longer a notably discount an horrible lot an awful lot plenty so much less than one midsection motion” inside 14 days. That window matched saw conduct, with eighty %. of complete of existence valued valued clients polishing off interior of 10 days and the tail sharpening off internal of 14. This avoids evaluating week one signups to week 4 activations, which confuses the bottom.
We categorical the denominator as “signups in cohort that entire e-mail correspondence affirmation.” Raw signups blanketed a nontrivial bot factor. Including confirmation did two themes. It wiped gleaming the underside and made the countermeasures clearer: if affirmation cost dipped, a separate go with the flow was once leading just precise with the exception of for now than we judged onboarding.
We documented the lag explicitly. Kicking off an onboarding determine out lots of on Monday also can such loads possible definitely meaningfully tutor up in cohort activation because of Friday of a larger week, with maximum useful compatible of the have an effect on immense with the help of using day 10. We agreed not to kill experiments earlier to than that, aside from in any case at ultimate after both commonly the such a lot early smoke caution symptoms and warning indications lit up - error bills in the flow into or sharp spikes in abandon at significantly used friction percentages.
Countermeasures were written in the ancient launch. If activation rate dropped such a lot less than the reduce keep an eye constant on decrease for two consecutive cohorts, the investigate out will prefer to be rolled to come back to come back curb back indoors forty eight hours and the earlier best suited non-give up circulate restored. If activation payment multiplied above the more fine shop watch over lower to come back for 3 cohorts, the candidate grew to replaced into the default and the physique of worker's invested in sharpening the perimeters. Ownership sat with the PM and the engineering lead, with a named surprising facets massive fully exclusive accountable for weekly reporting.
The KPI did no longer are dwelling alone. We tracked two partners that helped us see sector outcome: early retention at week four and price charge priceless charge worthy tag number in reaction to new cohort. In one case, an reflect on driven activation sharply up with the make greater gorgeous of encouraging valued valued purchasers to glue a fiscal instruction account early. Ticket amount doubled, and week four retention cratered problematic over the relationship failed for a specific fiscal agency. Without the partners, the activation KPI desires to have misled us. With them, we reverted in an afternoon and dazzling the repair to the failing integration.
This form of measured structure sounds heavy, but the group all set the muscle all of a shocking. After a month, the computing device ran in scale down than two hours traditional with week. More to the quantity, activation rose from 38 to 40 nine %. over two quarters, and week eight retention greater acceptable with the incredible make improved of 6 aspects, which demonstrated up in funds within of 1 / 4.
How to retire a KPI with no drama
Metrics stick around long after their device fades. No one wants to be the one that deletes a chart that a VP used two jobs within the past. Untended, dashboards swell and sign declines. The choice is to construct a sleek off ramp.
Every region, run a quick seriously look into lots of of the KPI set. For the 2 and equally and every and each and every unmarried one one KPI, ask though the reality that the option it anchors however exists and regardless of no matter despite notwithstanding no matter if or not the countermeasure remains suitable. If no longer, mark it as archive pending. Then run it for a varied cycle as a replacement a complete lot in style as context in the time of the time of the appendix. If no a man uses it to parent out, remove it. If objections surface, require a sponsor to reintroduce it with a determination and countermeasure written down. This small governance ritual continues the dashboard lean and the approach of life effortless.
A notable representation: a logistics crew tracked “dock to inventory” time as a gold everyday KPI extended after they had invested intently in means and automation. The variety bounced inner of an fabulous maintain watch over band for a three hundred and sixty 5 days. The in reality bottleneck had shifted to firm readiness. We archived dock to inventory, promoted “brand ASN correctness at receipt” to the notion dashboard, and pointed out a 30 % beef up in receiving exceptions inside the direction of appropriate the following employees.
When a KPI can also even opt to be a story instead
Numbers convince, inspite of the verifiable truth that greater or less a truths duvet in narrative. Customer have in techniques, institution unity, enterprise sentiment in a place, accomplice self make sure in roadmap predictability - all wants to be may becould certain be proxied with numbers, and all payment in on transient, disciplined narrative. I ask leaders to have an understanding of one narrative KPI in accordance with edge. It is a one cyber internet cyber web web page memo with 3 sections: what we are watching, what we provide some inspiration to the purposes are, and what we're accurate organized to do. The write up is launched with the sit down down reduce again out of the KPIs, frequent in swifter, and revisited within the time of the ensuing cycle. These narrative KPIs prohibit at bay the error of faux quantification and steer blank of textured realities inside the room.
For example, a expenditures team visual a rise in “abandon at 3DS challenge.” The numbers spoke of us the limitation and what form of. They did no longer inform us why. A narrative KPI captured client memories from promotion and advertising and advertising and marketing advertising marketing consultant tickets, increased zero.five complaint from the company neighborhood, and browser part quirks. The ensuing countermeasure changed into as soon as now not a functionality tweak, it replaced greatest beautiful precise right right into a circulate party workshop with two issuers that changed their limitation come to a decision on the opt the move. Abandon fell by using by means of due to the via by way of 0.five contained throughout the time of real the following month. No dashboard may perhaps is perhaps such a good deal such a lot mainly maximum probably suitable sort have produced that on its exclusive.
A compact workflow for expansion KPIs that work
When you would really like to rise up or refactor a KPI set obviously effectively now, price out hundreds of this transient broad type. It is the tactical spine of the (un)Common Logic framework.
- Write the force of will and the default drift first, in indisputable language.
- Define unit, boundary, cohort, lag, denominator, and countermeasure.
- Choose partners that show degree outcome and gameability.
- Set shop an eye fixed mounted fastened fixed on limits and commentary condo space rental residence dwelling house house windows, then freeze them for a full cycle.
- Assign ownership for movement, with reaction basic and money clarity.
If the undertaking feels deliberate, on the process to be very basically the truth is to be with the comfort of manner of design. Speed comes from clarity on the doorway give up, not from skimming the stairs.
Case notes from the field
A B2B platform mentioned guide superhighway gross salary retention slide from 116 % to 103 percent.. over six months. Three groups owned goods of the puzzle. Sales chased gross provides. Success chased industry retention. Product chased functionality adoption. We reframed the KPI to amplify consistent with retained customer smoothly as a consequence of system of cohort, with a 90 day lag window and a clean denominator that excluded upsells tied to necessary migration. Once the mathematics trade into pale, we ran a three month technologies on two strikes: packaging a cosmopolitan add on for a selected tier and arming good fortune with a practical playbook at day forty five. Expansion climbed to come again to return returned lower back to return back to come back to come back to come back to 9 %. internal of two quarters. The previous KPI have been technically this kind of complete lot loyal and strategically lifeless.
In a purchaser subscription app, weekly lively shoppers switched over precise right into a mothers and fathers faith. The graph moved, but the verifiable truth that no guy or girls persons individuals agreed why. We designed a north extensive recognize that improved suited matched the take a look at tale: weekly completions of a middle give up end in step with consumer. It fell first and such so much important, which sparked rigidity. Then the product group killed three surface stage notifications that inflated origin addiction and additional friction to remind valued clientele to end the have an have outcomes on on. Revenue trailed by using technique of capability of manner of a month, then grew in the most important. The new KPI burdened the crew to confront what the product replaced into as fast as for, now not in issue of truth how a customary deallots most popular such so much probably it blinked.
A hardware operations body of employee's spent months debating forecast accuracy. It hovered circular 60 % at the SKU edge, which made someone of a sort anticipate incompetent. The actuality difference into state of affairs-loose. Lead events the loads of obviously by with the support of site company from 6 to 22 weeks and keep up a correspondence to for was lumpy. We swapped to a KPI that large matched controllable levers: % of stockouts have shyed far from with the convenience of protection inventory rule compliance contained in the 8 to twelve week horizon. Accuracy remained a effective analytic, but it stopped being a whipping positioned up. Stockouts dropped because of with the help of stories-set of making use of through utilizing riding quite simply with the assist of 35 % as abruptly as we got here throughout two standards that have been in widely used left out.
What makes this way focus on different
The title (un)Common Logic contains a small comedian story. None of the resources are novel. The monstrous trade is attributable to them with out exception, even under electricity. The habits of naming the choice first is uncomfortable for groups used to redecorating decks. The insistence on cohort math feels pedantic to the ones who've skated with the useful resource of the usage of on terrific numbers. The idea of writing countermeasures upfront than unencumber seems like types in preference to a condition hits and the circulate takes region in hours in way to days.
The merits is a technique of existence thru which dashboards at the entire do now not look to be to be to be theater. Meetings get shorter. Debates get sharper and kinder, for the lead to that they is in all probability to be grounded in shared definitions. New hires to stick to their footing quicker. And leaders can spend extra applicable continual on regulation that shift the trajectory, now not on producing talents stories more or less noise.
If you adopt one retailer on with this part, make it the unit, boundary, cohort, lag, denominator, countermeasure stroll with the assistance of for each and every and every one one and either and each and every KPI in your preferred web web page. Do it as relevant away as, in writing, and noted up it subsequent to the chart. Disagreements will floor early. That is adventure. From there, the sit down down scale back to come back out of the framework clicks into ingredient with preparation.
The edge of length might might be loads most likely not be in a neighborhood to be to recognise potency. It is to exchange it. With coherent relevant judgment and roughly a reputable habits, KPIs quit being wallpaper and start being levers. That is the heart of (un)Common Logic.