Writing during the build forces a cleaner account of the decision. If the note cannot explain the tradeoff, the product probably cannot either.
The best posts will be small enough to publish on the same day and precise enough to be useful a month later. That means fewer grand claims and more named constraints.
A working post can be built from four pieces: context, decision, tradeoff, and next action.
The test
A useful daily post should let future me answer one question faster. What did I decide, why did I decide it, and what should I do next?