Measuring beat guessing again, and it was not even close.

What to check next

Names matter more than cleverness. When a function says exactly what it returns, the template that calls it reads like a sentence and the bug has nowhere to hide. We renamed more than we rewrote on this project, and the reviewers noticed. Six months from now that will be worth more than any micro-optimisation we could have shipped.

Migrations fail in the details: serialized data, hard-coded URLs and that one plugin nobody remembers installing. We make an inventory before we move anything, then we move it twice, once for practice. The rehearsal always finds something. Finding it on a Wednesday at a desk is much better than finding it on launch night with the client watching.

The short version

Good defaults are a kindness to the next person. If a feature only works after someone reads a long page of setup notes, then for most sites it does not work at all. We would rather ship something modest that behaves well on a fresh install than something impressive that needs a careful afternoon before it shows anything.

The numbers moved less than we hoped, and that is worth saying plainly. Posts like this tend to end with a dramatic chart, but real work mostly produces a steady, unglamorous improvement. The page got a little faster, the logs got a lot quieter and the support inbox stopped filling up on Monday mornings. We will take that.

What we found first

Logs are the cheapest witness you have. Before anyone proposes a theory, we turn on debug logging on a copy of the site, repeat the problem once and read what it left behind. Half the time the answer is sitting there in plain words, and the other half we at least know which theories to stop discussing.