Lately, I’ve seen a recurring anti-pattern across several different scrum teams. The pattern works likes this: a team forecasts a certain number of points per sprint and regularly completes that same number. If you were to plot the team’s hit rate, or number of points completed over those forecasted, then you would see a fairly straight line at 100%. The plot below represents a team who, after an erratic first few sprints, has settled down to a particular 100% hit rate.
From the outside, it looks like the team is right on track. But, as they begin to near the end of the release, everyone starts to realize that the picture isn’t quite as rosy as first thought. In fact, it becomes obvious that they’re not on track at all to complete all planned work in time for the release, even though they had consistently completed the same number of points they had forecasted. How does this happen?
Finding the Churn
This can occur when the team regularly accepts new work during the sprint that pushes the planned work to the side. This work, which often takes the form of high priority bugs or customer issues in production that must be fixed immediately, is estimated and added to the sprint alongside the existing work. Often, this “high priority” work pushes the previously scheduled work to the side. At the end of the sprint the team celebrates completing the right number of points…unaware that they actually completed the wrong points.
How can we catch this before we near the end of the release so we can do something about it? By tracking “point churn”. Churn is the number of points added to a sprint after it has begun. Typically, we discourage adding work to an in progress sprint but some teams follow this practice to handle high priority work that must be addressed quickly. These teams can get early insight into their churn by plotting the number of points added to their sprint alongside their hit rate.
The plot to the right adds an additional line along side hit rate to indicate point churn. The red line, bound to the right axis, represents the number of unplanned points added each sprint. You can see that although the team maintains its 100% hit rate, more and more points have been added each sprint. This could be an indicator that although the team is completing the right number of points each sprint…they could actually be completing the wrong points.
If you notice that your hit rate is consistently around 100% but your churn is regularly above 0 then this is can be an indicator that you’re falling behind in your overall release, even though you’re completing the planned number of points each sprint.
A Simpler Approach
But there is another approach. Rather than go to the effort to track unplanned work that is added to each sprint, an alternative approach is for the team to still accept the unplanned work but not award any points to it. In this model the work is not added to the sprint, but it is still tackled alongside sprint work. This approach is easier since it doesn’t require tracking additional points and, if the team reaches the end of the sprint and still has planned work outstanding as a result of being distracted by the unplanned work, then the hit rate for the sprint actually provides a more accurate reflection of how the team is likely to pace for the overall release.
To make new work more visible in this approach you can even add an additional lane to your sprint board for it to flow through. Seeing this work alongside your planned work, especially with team members assigned to it and Work in Progress limits respected, is a wonderfully effective way to illustrate the impact that new additions can have on your sprint plan.
In the image above, we’ve added an empty row to the bottom of the standard scrum board to allow unplanned work to flow across the board. These cards are red to indicate their importance. However, note the WIP limits for each state called out in parenthesis at the top. Deploying has a WIP limit of 1 meaning, that the unplanned work is currently blocking release of the planned work for the sprint. Adding an explicit lane to the scrum board can more visibly call out the effect that unplanned work has on a team’s productivity rather than the team simply accepting the work but then quietly falling behind.
Whichever approach you choose, asking whether your team is completing the right points instead of just all of the points can provide early insight into your team’s pace and give you the opportunity to correct your course before its too late.