Product backlog refinement—sometimes called product backlog grooming in reference to keeping the backlog clean and orderly—is a meeting that is held near the end of one sprint to ensure the backlog is ready for the next sprint.
During a product backlog refinement meeting, the team and product owner discuss the top items on the product backlog. The team is given a chance to ask the questions that would normally arise during sprint planning:
- What should we do if the user enters invalid data here?
- Are all users allowed to access this part of the system?
- What happens if…?
By asking these questions earlier, the product owner is given a chance to arrive at answers to any questions he or she may not be prepared to answer immediately.
If those questions were asked for the first time in sprint planning, and too many could not be answered, it might be necessary to put a high-priority product backlog item aside and not work on it during the sprint.
These questions do not need to be fully resolved in a backlog refinement meeting. Rather, the product owner needs only to address them just enough so that the team feels confident that the story can be adequately discussed during the coming planning meeting.
Backlog refinement in that sense is really a checkpoint rather than an effort to fully resolve issues.
I like to hold the product backlog refinement meetings three days before the end of the current sprint. This gives the product owner sufficient time to act on any issues that are identified. Some teams find that doing shorter meetings every week rather than once per sprint are more suited to their cadence, and that is, of course, fine.
Unlike other Scrum meetings, I do not think the product backlog refinement meeting requires the participation of the whole team.
If you think about a whole team meeting three days before the end of the sprint, there is likely to be someone who will be frantically busy—someone who, if forced to attend one more meeting, may have to work late to finish the work of the sprint.
I’d prefer to conduct the meeting without such team members. As long as the same team members don’t miss the meeting each sprint, I think it’s fine to conduct backlog refinement meetings with about half the team plus the product owner and ScrumMaster.