“An adequate ScrumMaster can handle two or three teams at a time...A great ScrumMaster can handle one team at a time.”
One of the lessons we learned early in our Scrum roll-out was that the Product Owner and Scrum Master roles required much more involvement than originally thought. Coming from a Waterfall development environment, where releases were long in duration and milestones spread out, people in the organization were used to having key roles on multiple projects, context switching as needed. Juggling responsibilities in a Waterfall environment seemed to work well, or at least acceptable. Our Product Managers, for example, could own several product lines, including associated customer meetings and field interactions, and easily satisfy occasional project touch-points such as requirements definition (at the beginning of the release) and Beta and FCS duties (at the end of the release). These project touch-points required their full-time involvement periodically, a few times a year, making it relatively easy to context-switch periodically and satisfy the needs of each effort.
With Scrum, however, things turned out a bit different. Though we “took the training” and “read the literature” which repeatedly said the roles of Scrum Master and Product Owner were full time jobs, we weren’t true believers. Our “muscle memory” way of working had everyone juggling multiple roles and responsibilities, it was the way we were used to working. During the course of our Agile Pilot projects, however, we got convinced pretty quickly that Scrum roles could not be part-time.
Scrum is more intensive than waterfall development.
With frequent “potentially shippable product increments” created every 2-4 weeks, there’s essentially a full product release at least once a month if not twice. During our Agile pilots, our Product Managers, filling the role of Product Owners, soon realized that creating and maintaining a Product Backlog required a significant amount of time. Every few weeks a new set of fully-defined “product requirements” need to be ready for the team for the next Sprint. Product Owners found it challenging to satisfying their Scrum PO role and concurrently complete other project work. Our Scrum Masters, too, found themselves booked full-time, facilitating team interactions, producing Sprint Burn Down charts, working impediments, and delivering frequent product releases at regular Sprint Review. Team members, often with other-project responsibilities, found themselves spending more time delivering on Sprint Goals, often at the expense of their other responsibilities.
As we scale Scrum within the organization, we’ve (obviously!) needed to identify new Scrum Masters and Product Owners. We’ve held fast to the one project per Scrum Master recommendation. Identifying new dedicated Scrum Masters has been fairly easy - our Pilot teams was that the efforts produced several Scrum Master candidates, a nice side-benefit! Finding full-time Product Owners for each team was more challenging. Because we’re applying Scrum to large multi-team projects, our mapping of Product Manager positions to Product Owners simply didn’t scale. Our solution was to look to our lead engineers. Most of our new teams have technical Product Owners, usually Software Architects, and they are dedicated full-time to the team. Product Managers are involved at either a co-Product Owner (in an outward facing role) or at a higher level in the project effort, via a Product Council-type role that involves them as stakeholders.
I expect our organization to fine tune (via inspect and adapt) these non-Scrum roles as we mature in our Agility. But regardless of the organizational “noise” around the Scrum Teams, I believe that participation at the Scrum Team-level will continue to require full-time effort from all members in order to be successful.