Keep a Decision Journal and Find Out How Good You Actually Are
I used to think I had good judgement. Everyone does; it’s one of those things nobody rates themselves below average on. Then I started writing decisions down at the time I made them, with my reasoning, and reading them back six months later. It was humbling in a way I hadn’t expected.
Not because the decisions were bad. Many were fine. It was the reasoning. I’d remembered being thoughtful. The log showed I’d often been hurried, overconfident, or swayed by whoever I’d spoken to last. The outcomes had hidden that, because good outcomes make us remember good reasoning that wasn’t there.
What goes in
Only decisions that matter: hiring, money, direction, anything that’ll still be felt in a year. For each, a few lines at the time. What I’m deciding. What I expect to happen, specifically. How confident I am, as a number. What would make me wrong. How I’m feeling as I decide, because that turns out to matter more than I’d have guessed.
Ten minutes. Then close the book and don’t look at it.
The review
Every six months, read back the entries old enough to have played out. Compare what I expected with what happened. Not to score wins and losses; outcomes have luck in them. To check the process. Was the confidence justified? Did the thing I said would make me wrong actually happen, and did I notice? Was I deciding or was I just tired?
What mine showed
I’m well calibrated on technical decisions and badly overconfident on people. I decide worse after four in the afternoon. I consistently underestimate how long things take, by about half, even when I’ve adjusted for underestimating. And nearly every decision I regret was made within a day of someone pressuring me for an answer. None of that was visible from memory. All of it was obvious from twenty entries.
Why it works
Hindsight is a liar. Once you know how something turned out, you can’t un-know it, and your memory of the decision quietly reshapes itself to fit. The written entry is the only witness that can’t be bribed. It says what you actually thought, with the confidence you actually had, before reality voted.
What it changes
Once you know your patterns, you can build around them. Big people decisions now get a second opinion from someone less trusting than me. Nothing important gets decided after four. Every estimate gets doubled. And when someone wants an answer today, the answer is tomorrow, because the log showed what today’s answers cost.
Keep it private
This only works if it’s honest, and it’s only honest if nobody else reads it. Write the confidence you actually feel, not the one you’d admit to. Write the real reason, including the petty one. The journal is for calibration, not for show.
Start with the next one
The next decision you’ll still be living with in a year: ten minutes, five questions, then close the book. In six months you’ll know something about yourself that memory would never have told you.
Launch list
Be there on day one.
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The book itself — 40 laws in ten parts, 320 pages, each ending with The Work — is funded first on Kickstarter.