A Sprint should be short enough to allow the Scrum Team to maintain focus but long enough to deliver an Increment that meets the Definition of Done. If a Sprint is too long, the definition of what is being built may change, and complexity and risk may increase. Conversely, if Sprints are too short, it may not be possible to produce an Increment that meets the Definition of Done.
Typically, each Sprint is a short Project with a fixed amount of time to convert an idea or need into something valuable. Shorter Sprints generate more learning cycles and limit the risk of cost and effort. However, longer Sprints provide more room to accommodate uncertainty. Most common Sprint durations are around two weeks, which suits over 80% of Scrum Teams.
