Question
Why does decision journal fail?
Quick Answer
Recording only the decision without the reasoning. A list of 'what I decided' is a changelog, not a decision journal. The value lives entirely in the 'why' — the assumptions, the constraints, the alternatives considered. Without that context, your future self has nothing to evaluate and nothing to learn from.
The fix: Pick one decision you made in the past week — it doesn't have to be big. Write down: (1) what you decided, (2) the 2-3 reasons that drove the decision, (3) what you expected to happen, and (4) what alternatives you rejected and why. Time yourself. This should take under 5 minutes. If it takes longer, you're over-thinking the format and under-practicing the habit.
The underlying principle is straightforward: Record not just what you decided but why — because your future self will rewrite the reasoning after the fact, and you will never notice it happening.
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Go beyond the answer
This topic is part of Think With AI — a guided sequence of 16 lessons.
After completing this path you will use AI as a thinking partner without judgment atrophy: your mental models and assumptions externalized where AI can challenge them, recurring decisions routed through explicit frameworks, decisions captured with their reasoning so both you and the AI learn from outcomes, and a clear line around the judgments that stay yours.
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