When you encounter debt — a stale comment, a drifted convention, a dead test, a number that collides, a guard nobody wired up — fix it, whether or not it belongs to the thing you came here for. Leaving the shared space tidier than you found it takes precedence over staying inside your task’s boundary.
The principle exists because the default is the opposite, and the default is expensive. Debt survives not because anyone decided to keep it but because every individual encounter with it was, reasonably, someone else’s problem — so the cost is paid over and over in small amounts by people who each correctly concluded it wasn’t theirs to fix. If not me, then who? If not now, then when? is the whole argument, and the answers are usually nobody and never.
This matters most in a record, because a record’s debt is invisible while the machinery still runs. An instruction that stopped being true, a citation to a document that moved, a status nobody flipped — none of it fails a build, and all of it costs the next reader.
Two rules keep it from becoming license to sprawl:
- Repair, don’t redesign. Picking up litter is not remodelling the building. If the tidy-up turns out to be a decision rather than a repair — it needs a decision record, or it changes behaviour someone relies on — file it rather than smuggling it in.
- Say what you picked up. An unexplained unrelated change in a diff reads as noise, or worse as a mistake. One line in the commit message turns it into a gift.