The software world
Scope creep
Work quietly growing past what was actually asked for. In a plan it looks like a helpful extra step — tidy up the old handler, rename these while we're here, restyle the neighbouring page — attached to a request that never mentioned any of it.
Why it matters
Part of Tasks too big for one prompt → It's the single most common thing worth catching when you read a proposed plan, because it's the failure that sounds like diligence. Every extra step is more files touched, more to review, and more that can break somewhere you weren't watching. The fix is one sentence — "skip step 4, don't touch `server/`" — and it only costs a sentence while the plan is still a plan.
see also