A ceremony, on the other hand, is driven by the clock.  Once the clock expires, the meeting is over regardless of the outcome.  Ceremonies are not all that bad.  For instance, we can have a ceremony to celebrate a significant accomplishment, discuss a change in strategy or review the results of a project.  What we have to watch out for are meaningless ceremonies that just consume time.

Scrum has a great deal of ceremonies – Daily Scrum, Sprint Review, Retrospective and Sprint Planning.  Even the Sprint itself could be considered a ceremony since when it expires, the Sprint is over.  However, just because they are ceremonies, it does not mean the pieces of Scrum are useless wastes of time.  Each ceremony in Scrum has a specific purpose that must be achieved before the close of the timebox and provides meaning to the ceremony.  The tkmeboxes which call each ceremony to a close are present to encourage focus, rhythm, accountability and commitment on part of the participants.

As a review, here is the list of the Scrum ceremonies, a short summary of the purpose and the guidance on the length of the timebox.

  1. The Sprint: an iteration to produce and deliver the potentially shippable increment.  The maximum timebox for a Sprint is thirty days.
  2. Sprint Planning: conversation at the beginning of each Sprint to decide what will be delivered and demonstrated at the Sprint Review.  Sprint Planning is not allowed to exceed eight hours for a thirty day Sprint.
  3. Sprint Review: conversation at the end of each Sprint to provide feedback on the product.  There is no specific guidance on the length of a Sprint Review in Scrum, but there is an implicit upper limit of four hours for a thirty day Sprint.
  4. Retrospective: conversation at the end of each Sprint for the Team to reflect and look for improvements.  Again, no specific guidance on the length of a Retrospective in Scrum, but there is an implicit upper limit of four hours for Retrospective for a thirty day Sprint.
  5. Daily Scrum: a daily gathering for the Team to see if they are on-track or off-track on their delivery of the Sprint Goal before the end of the Sprint.  It is a rule in Scrum that the Daily Scrum does not exceed fifteen minutes.

Generally, we do not extend the timebox of the Scrum ceremonies since we want people to learn how to achieve the purpose within the given time.  Breaking timeboxes is normally a behavior we are trying to fix with the introduction of Scrum, so allowing it to continue would be counterproductive.  Not to mention breaking the timebox of a ceremony would diminish the values and principles of Scrum – mainly commitment, accountability and rhythm.  Of course, if we achieve the purpose of the ceremony before the end of the timebox, people are free to go.

However, if the goal of the ceremony has not been met, the participants could choose to extend the timebox until the goal has been achieved.   The only ceremony that I would be extremely hesitant to extend would be the length of the Sprint itself.  This rhythm is so essential to the proper functioning of Scrum, I would need a VERY compelling reason to break the timebox.  It has happened and I have done it – it is just not that common.  For everything else, if the participants felt extending the timebox by a specific amount would be helpful to achieve the purpose, I would go with the judgement of the participants.