Good engineers plan before they build. The workflow I grew up seeing: write an RFC describing the feature, split it into smaller issues, then build them, each issue often blocking the next. The structure of the work was locked in before a single line of code existed.

This is reasonable. It keeps code reviews manageable and avoids big-bang merges. It also asks you to make your most critical structural decisions at the moment you know the least about the problem.

Before you've built anything, you're guessing: which pieces are separable, how complex each one will be, whether step 3 will force you to rethink step 1. Sometimes you're right. Often you're not, and step 1 gets thrown away. You learned something building it, but you'd have learned it faster by building the whole thing first.

We paid that cost for a good reason: the alternative was building everything and untangling it by hand, and untangling a week of work is harder than planning ahead.…