A good decision that turns out badly is still a good decision. A bad decision that turns out well is still a bad decision. Everyone agrees with this in the abstract and almost nobody operates on it, because outcomes are loud and legible and the reasoning behind them is neither.
I run a personal investing practice on the opposite convention. Every decision gets written down before it happens — the thesis, the counterargument, what would make me wrong — and then, at ninety days, gets graded on the reasoning rather than the result.
It is the single most useful habit I have, and it has almost nothing to do with money.
Why the result is a terrible teacher
The problem with grading yourself on outcomes is that the feedback is honest but the attribution is garbage.
You made a call. Some months later the number went up. Did it go up because your reasoning was sound, or because a thing you didn’t foresee happened to break your way? You genuinely cannot tell from the outcome, and here’s the trap: the answer you’ll reach for is the flattering one. Not because you’re dishonest — because the flattering explanation is the one that comes to mind first and there’s no mechanism forcing you past it.
Do that for a few years and you have built a confident, well-rehearsed account of your own judgment that bears no fixed relationship to your actual judgment. Then you make a large decision on the strength of it.
The fix is boring. You write down the reasoning at the time, while you still don’t know how it ends, and you grade that.
Write it down before you need it
The rules are the same idea one level up: decide the policy in the calm, not in the moment.
Mine are three. Sizing beats picking — how much you commit matters more than what you commit to, and it’s the part people spend the least time on. Sell discipline beats buy thesis — everyone has an entry story and almost nobody has written down what would make them leave. Grade decisions, not outcomes — this one.
The reason to write them down early has nothing to do with being organized. It’s that the moment you need a rule is precisely the moment you are least equipped to write one. When a position is down forty percent, you are not a neutral party evaluating a policy question. You’re a person looking for permission. A rule written eighteen months earlier by someone who had no stake in this specific bad afternoon is the only version of you qualified to make that call.
There’s a mechanical version of the same principle in the system: scores never trade. The scoring model produces a number, and the number’s only job is to feed a written memo. The memo gets a human decision at the bottom. The system has read-only access to everything and execution authority over nothing, and that line is not negotiable — not because I don’t trust the model, but because the day I let it act is the day I stop being able to grade my own reasoning, since I’ll no longer be doing any.
It generalizes further than it should
I did not expect this to be a general-purpose idea. It is.
When I brought an eight-year-old tractor under management, the same rule appeared in a different costume. An overdue filter didn’t get changed that week — parts, timing, season, and I made the call to defer it. Which, stated plainly, is what I had been doing for thirty-one months. The difference is that this time the deferral was recorded, with a date and a reason, and the overdue flag stayed up where I could see it.
Procrastination and planned deferral are the same inaction. What separates them is a timestamp and an owner.
That’s grading decisions instead of outcomes, applied to maintenance. The outcome in both cases is identical — the filter is still in the machine. The decision is completely different, and only one version of it can be reviewed, argued with, or improved.
The same thing runs an organization. Most places I have worked are excellent at deciding to do things and terrible at deciding to not do things. The not-doing happens anyway. It just happens by default — unwritten, unowned, and impossible to revisit, because nobody ever actually chose it.
What it’s really for
I’m teaching my sons the same thing without ever using the word.
You planted late. The frost doesn’t care. You skipped the scouting. The woods are quiet. Consequences arrive on schedule, calmly, without a lecture from Dad — and the lesson is never “you got a bad result.” It’s that the result was determined by a decision made weeks earlier that you didn’t know you were making.
Catch yourself at the decision and you can change something. Catch yourself at the outcome and all you can do is have a feeling about it.
That’s the whole discipline. Write it down before you need it, grade the reasoning rather than the result, and record the things you chose not to do. None of it is complicated. It’s just that all three are least appealing at exactly the moment they matter most.
This describes a personal practice. It is not investment advice — I’m not a licensed anything, and my rules are calibrated to my life, not yours.
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