Keeping the reasoning with the result

A result travels farther when the reasoning behind it can travel too. A chart without its definitions, a design without its constraints, or a recommendation without its assumptions becomes harder to use as it moves away from its author.

Write down the decision

Good documentation does not need to record every conversation. It should explain the decision, the alternatives that mattered, and the evidence that could cause the decision to change.

This gives future collaborators something more useful than instructions to copy an existing pattern. It gives them a way to recognize when the pattern no longer applies.

Preserve the counterexamples

A failed test is a description of a boundary. Keeping it makes that boundary available to the next person, who might otherwise rediscover it at a more expensive moment.

Make the next step visible

Every useful note should help someone continue the work. That might mean an open question, a reproducible example, or a clear statement of what remains unverified.

The aim is not exhaustive documentation. It is continuity: enough context that the next contribution can begin where the previous one ended.