To get a good, DEEP product backlog, we must proactively manage, organize, administer, or, as it has commonly come to be referred to, groom the product backlog.
What Is Grooming?
Grooming refers to a set of three principal activities: creating and refining (adding details to) PBIs, estimating PBIs, and prioritizing PBIs.
Figure 6.6 illustrates some specific grooming tasks and how they affect the structure of the product backlog.
Figure 6.6. Grooming reshapes the product backlog.
At the appropriate time, all PBIs need to be estimated to help determine their order in the backlog and to help decide whether additional refinement work is warranted. Also, as important information becomes available, new items are created and inserted into the backlog in the correct order. Of course, if priorities shift, we’ll want to reorder items in the backlog. And as we get closer to working on a larger item, we’ll want to refine it into a collection of smaller items. We also might decide that a particular backlog item is just not needed, in which case we’ll delete it.
Who Does the Grooming?
Grooming the product backlog is an ongoing collaborative effort led by the product owner and including significant participation from internal and external stakeholders as well as the ScrumMaster and development team (see Figure 6.7).
Figure 6.7. Grooming is a collaborative effort.
Ultimately there is one grooming decision maker: the product owner. However, good product owners understand that collaborative grooming fosters an important dialogue among all participants and leverages the collective intelligence and perspectives of a diverse group of individuals, thereby revealing important information that might otherwise be missed. Good product owners also know that by involving the diverse team members in the grooming, they ensure that everyone will have a clearer, shared understanding of the product backlog, so less time will be wasted in miscommunications and handoffs. Such collaborative efforts also go a long way toward bridging the historical gap between the business people and the technical people.
Stakeholders should allocate a sufficient amount of time to grooming based on the nature of the organization and the type of project. As a general rule, the development team should allocate up to 10% of its time each sprint to assisting the product owner with grooming activities. The team will use this time to help create or review emergent product backlog items as well as progressively refine larger items into smaller items. The team will also estimate the size of product backlog items and help the product owner prioritize them based on technical dependencies and resource constraints.
When Does Grooming Take Place?
The Scrum framework only indicates that grooming needs to happen; it doesn’t specify when it should happen. So when does grooming actually take place?
Using sequential development, we try to capture a complete and detailed description of the requirements up front, so little or no requirements grooming is scheduled after the requirements have been approved. In many organizations these baselined requirements may be changed only via a separate change control process, which is discontinuous to the primary development flow (see Figure 6.8).
Figure 6.8. Outside-of-primary-flow grooming with sequential projects
As such, grooming during sequential development is an exceptional, unplanned, outside-of-primary-flow activity that we invoke only if we need to, making it disruptive to the fast flow of delivered business value.
Using Scrum, we assume an uncertain environment and therefore must be prepared to constantly inspect and adapt. We expect the product backlog to evolve constantly rather than being locked down early and changed only through a secondary process for handling exceptional, undesirable occurrences. As a result, we must ensure that our grooming activities are an essential, intrinsic part of how we manage our work.
Figure 6.9 illustrates the various times when grooming might be performed.
Figure 6.9. When grooming happens
Initial grooming occurs as part of the release-planning activity (see Chapter 18 for details). During product development, the product owner meets with the stakeholders at whatever frequency makes sense to perform ongoing grooming.
When working with the development team, the product owner might schedule either a weekly or a once-a-sprint grooming workshop during sprint execution. Doing so ensures that grooming occurs on a regular schedule and enables the team to account for that time during sprint planning. It also reduces the waste of trying to schedule ad hoc meetings (for example, determining when people are available, finding available space, and so on).
Sometimes teams prefer to spread out the grooming across the sprint, rather than block out a predetermined period of time. They take a bit of time after their daily scrums to do some incremental grooming. This grooming doesn’t have to include all of the team members. For example, after a daily scrum the product owner might ask for help refining a large story. Team members who are knowledgeable and interested stick around and assist the product owner. The next time, different team members might assist.
Even if teams have regularly scheduled workshops or take some time each day to look at the backlog, most teams find that they naturally do some grooming as part of the sprint review. As everyone involved gains a better understanding of where the product is and where it is going, new PBIs are often created or existing PBIs are reprioritized, or deleted if they are no longer needed.
When the grooming happens is less important than making sure it is well integrated into the Scrum development flow, to ensure flexible and fast delivery of business value.