What should the Scrum Master do if the time-box of event has already expired, but the goal not reached yet?
This is the quote that made me think about this question:
So what do we do when the time-boxed sprint planning meeting is nearing the end and there is no sign of a sprint goal or sprint backlog? Do we just cut it short??? Or do we extend it for an hour? Or do we end the meeting and continue the next day?
This happens over and over, especially for new teams. So what do you do? I don’t know. But what do we do? Oh, um, well, usually I brutally cut the meeting short. End it. Let the sprint suffer. More specifically, I tell the team and product owner “so, this meeting ends in 10 minutes. We don’t have much of a sprint plan really. Should we make do with what we have, or should we schedule another 4-hour sprint planning meeting tomorrow from 8 am?”. You can guess what they will answer... :o)
I’ve tried letting the meeting drag on. That usually doesn’t accomplish anything, because people are tired. If they haven’t produced a decent sprint plan in 2 – 8 hours (or however long your time-box is), they probably won’t manage it given another hour. The next option is actually quite OK, to schedule a new meeting next day. Except that people usually are impatient and want to get going with the sprint, and not spend another bunch of hours planning.
So I cut it short. And yes, the sprint suffers. The upside, however, is that the team has learned a very valuable lesson, and the next sprint planning meeting will be much more efficient. In addition, people will be less resistant when you propose a meeting length that they previously would have thought was too long.
Scrum and XP from the Trenches. How we do Scrum. By Henrik Kniberg.
In reality, I think, there are only two possible solutions: To add some time to event or just interrupt it.
These are my ideas and what I did in my practice (my solutions may be wrong, that's why I asked this question):
Daily Scrum. In really, I never had problems with time-box limit of Daily Scrum. But I have no objections to interrupt this event after 15 minutes.
Sprint Planning. All that Henrik Kniberg wrote makes sense. But in my practice, I always just add some additional time. This problem happened very rare in my practice (but nevertheless has happened). It happened at the beginning of projects when Product Backlog is not yet well-refined. Much more often we spend much less time than Scrum Guide prescribes (which may be not good either, but that is another question).
Sprint Review. This problem happens with me during Sprint Review more often than during Sprint Planning. Interrupt it and make new session on next day? No, thanks. It will be a painful to gather all stakeholders on unusual day. Don't make new session at all? It may harm next Sprint. So, I always added some additional time, if time-box is not enough. If it is not right decision, please correct me.
Sprint Retrospective. As in a case of Daily Scrum, I have no objections to interrupting this event if time-box is expired.
About Product Backlog refinement: In reality, I never calculated exactly what percentage of capacity it took. But I think there is nothing terrible about it being more than 10 percent, especially toward the beginning of the project.