Estimating in Story Points

Occasionally an established team will have an addition of one or more team members. They might be inexperienced and so the Story Point estimation topic needs to be revisited by the team’s Scrum Master to explain the mechanics and help the team plan Iterations reliably.  It is natural, for the team to jump to conclusion that if an inexperienced team member will work on a story, then this person’s estimation will be larger. However, what we need to remember is that the new team member takes into consideration not the Volume and the Complexity, but the gap in their experience. Their estimation is based on “unknowns”. So should we adjust the points on stories that this new team member will work on? 

Perhaps a better approach would be to engage the team members in the Pair Working activity. That way, the experienced team member can take the Story that the team has agreed is the baseline estimated as One (in Story Points) and demonstrate to the new team member why this particular Story is “1” in both Volume and Complexity.  Having gained this understanding, the new team member will be able to either estimate the Stories relative to the One or abstain from the vote if the Story is not well understood (this is the reason most of the Planning Poker packs have a card with a question mark on them).

What does it mean for the team’s Iteration Planning?

The biggest gain from baselining Story Points for the whole team is the ability of Scrum Master to observe the team’s growth and experience in the work they are dealing with. Simply put, an inexperienced team will take longer to deliver during an iteration five Stories estimated as one point when they are just starting up. As learn and gain new knowledge, they will be able to go through more stories. Looking at the velocity metric we will then observe that an average velocity per Iteration will grow over time. Bearing this in mind, it is natural to expect that adding new team members will mean that, in the beginning, the team’s velocity will take a hit (which in itself is an important context for the metric). The inexperienced team members will take longer to deliver a Story estimated as One. The experienced team members will also spend more time delivering their work because they might be Pair Working with new team members and spend time teaching them. All of these should be taken into consideration when planning Iterations. 

So how long should a new team member engage in Pair Working? This will depend on various factors. If the type of work that the team is dealing with is constant and familiar to them, it might be that the new team member will only need to spend the first iteration Pair Working with other team members to understand the range of Volume and Complexity of work the team is dealing with. On the other hand, we are dealing with the individual’s level of skill, knowledge and ability to learn. A practical approach is required. It is ok to rely on the more experienced team member for advice when planning a new iteration. The experienced team member might be able to identify a Story that the new team member should be able to work on and deliver based on what they have learnt.  

In conclusion - It is not recommended that the team adjusts the Story Points based on the lack of experience of the new team members. Once the team agrees on what a One Story Point piece of work means in terms of Volume and Complexity, this needs to be explained to the new team members so their progress can be visible.