A time box is a common practice underlying most agile processes especially, Scrum. Time boxing is a the closest thing in agile or scrum has to something that is a best practice. Most managers or early adopters of Scrum wonder what they do to create a sense of urgency and the answer is simple “Time Box”.
In Scrum we have 6 formal time boxed events.
Other time boxes can be applied and should be. The purpose of the time box is to cause movement and to set an expectation that we will limit the time and energy spent in any one direction. Generally people will fall prey to taking on too much work or big amorphous work that has no discernibly edges or clarity. Our understanding is similarly fuzzy and vague.
We can use a time box for many things including as a guide line in how we break work down into tasks or execution. Sometimes people use time boxing as a way to avoid gold platting or excessive polishing of an item or thing.
Time box is a critical practice in agile / scrum and should be applied with care. Arbitrary time boxing can drive motivation down and should not be used as a tool to create a frenetic pace or fearful environment. Time boxing is an important tool for any good scrum master or facilitator.