The vocabulary
The Call Memo
The artifact
The call isn't made until it's written. That sentence is a rule, not a slogan, and here's the mechanism behind it: a decision that lives only in your head has no fixed form, so every morning's mood gets to redraw it. Same arguments, same 6am, no new evidence, and the toll comes out of the attention your actual work needed. Founders call this "still thinking it through." What's actually happening is the same lap of the same track, daily, at your most expensive hour.
The Call Memo ends it. One page, nine fields, written at the moment of deciding. Once the call is on paper with tripwires attached, doubt has a test to pass, and doubt without a tripped wire is weather.
The fields
CALL: one sentence, past tense: "I decided to..." DATE: today · WINDOW: what forced the timing WHY: 2-3 sentences a stranger could reconstruct the call from LOST: each rejected option + the one-line reason it lost CURRENCIES: the worst case accepted in each currency the call touches EVIDENCE: what you knew, marked fact or feeling · the base rate TRIPWIRES: the state + date that reopens this FIRST 24H: who gets told, what changes immediately, first action REVIEW: the date this call gets graded
Every field is load-bearing, but three do work nothing else in your toolkit does:
LOST records the options that didn't win, and why. Without it, the review two quarters from now can't tell whether you chose well from a real set or rubber-stamped the only idea in the room. If nothing else was ever on the table, the memo says so, because single-option decisions fail at famously high rates and your future self deserves to know this was one.
EVIDENCE, marked fact or feeling. The memo records what you actually knew, including "this was a gut call." Dressing a feeling up as analysis doesn't improve the decision; it ruins the calibration data, and the calibration data is the compounding asset.
REVIEW. A memo without a review date is a diary entry. The date is what turns a record into a feedback loop.
Where it comes from
Asked for the single practice he'd recommend to any decision-maker, Kahneman told Michael Mauboussin: keep a decision journal, written at the moment of deciding, because hindsight quietly rewrites what you knew, and once it does, you can't learn from your own record. Memory is a motivated historian. It doctors the evidence in your favor, backfills reasons you didn't have, and deletes the warnings you ignored.
The operator demonstration is Lutke again: Shopify's COVID capacity bet, stated in writing as a falsifiable claim while he was placing it. When the 2022 numbers came in against it, the written record left exactly one honest move, and he made it in public: "placing this bet was my call to make and I got this wrong." Then the cut, in one motion. No written claim, and 2022 becomes a year of arguing with the evidence, because unwritten bets are infinitely renegotiable by the person who made them.
The habit that compounds
One memo helps one decision. The practice compounds into something bigger: ten memos in, you own a documented record of your own judgment that memory can't doctor. Which calls you rushed. Which currency you consistently underprice. What your "certain" actually converts at. That record is the raw material for calibration, and calibration, not intelligence, is what separates decision-makers who improve from ones who just accumulate anecdotes and confidence.
This is also why the memo's fields never change, whether the call got the full workup or thirty seconds of shower time: one format means one journal, and one journal means your history is comparable across every call you've made.
The rule that makes it work
Once the memo is written, deciding is over. Reopening without a tripped wire or genuinely new evidence gets named as what it is: relitigating, a tax you pay every morning for a purchase you already made. The memo isn't paperwork after the decision. It's the mechanism that makes the decision stay made.
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