Definition of done

A definition of done is the team's written agreement about what must be true before any item counts as finished: reviewed, tested, documented where it matters, deployed to staging, accepted by whoever asked for it.

Without one, "done" means whatever the person saying it assumed, and the difference surfaces at the worst moment — at a demonstration, or during a release, when three items described as complete turn out to need a day each.

It is also the defence against the pattern where everything is ninety per cent complete for a month. A shared, unambiguous bar makes progress real rather than reported, which matters more to a client than any burndown chart.