Definition of Done

Biological Parallel

Bird fledging has a clear definition of done: capable of sustained flight, not just leaving the nest. A premature fledgling that falls from the nest and can't fly is incomplete work that creates downstream costs (parental rescue efforts, predation risk). Successful fledging means the bird can thermoregulate, fly to safety, and find food independently—not 'mostly done' or '90% complete.' Definition of Done mirrors this completeness threshold: work isn't done until it meets all acceptance criteria (flight-capable), preventing technical debt (fallen fledglings) that burdens future sprints with rescue missions.