What is Timeboxing?
Timeboxing fixes the time and lets the content flex: the meeting is 15 minutes, the sprint is 2 weeks, the spike is 3 days — when time's up, you stop and work with what you have. It's the inversion of "work until done," and it weaponizes Parkinson's law instead of suffering it.
Every Scrum event is timeboxed, and the sprint itself is the master timebox: scope negotiates, the date doesn't.
Worked example
A team gives itself a three-day timebox to evaluate two mapping libraries. Day three ends with library A at "good enough, proven" — and the temptation to spend "just two more days" perfecting the comparison is refused by design. Decision made, building begins. Without the box, that comparison had a comfortable month in it.