A Scrum Master is not operating successfully when they:

• Operate as the manager of the Team: The Scrum Master is a coach, facilitator and protector. About the only power the Scrum Master has is to enforce the process - expect Daily Scrum meetings, Iteration Reviews, etc. are going to be held and the standard to which they operate.
• Are not engaged: The most under-rated aspect of the Scrum Master’s role is the idea that someone can help people get better as a team. Properly done, a Scrum Master can help a Team become much more than the sum of its parts and the additional productivity is typically much more than the person had contributed as another team member. For example, it is not unheard of for a Scrum Team to increase their productivity by more than 2X and 3X … I’ve seen 9X. See How Do Small Changes Lead to Big Improvements? for more of this thinking.
  • Note: Many people, without a complete understanding of the role, think that the Scrum Master is not a full time role. The problem is that a lot of what a Scrum Master does is hidden. But think about it: if your favorite sports Team needs to a coach to become more effective, why would this not be true for a Team doing (usually) more complex knowledge work.
• Operate as the Lean-Agile “Police”: Above all the Scrum Master is guided by the values and principles of Lean-Agile. They are pragmatic based on what the data is telling them. In particular if there is a specific practice that is not working, the role is not to insist on the practice, but rather work to determine to approach to take based on these values and principles to achieve the goal.
• Operate as the “Scrum Mom” or “Scrum Dad” role. Scrum Masters are not about doing all the work that the Team does not want to do (e.g. keeping the work management tool up to date, working all impediments, etc.). The Scrum Master doesn’t act as an arbiter when Team members point out the failures of other Team members, but rather works to have Team members deal with each other directly. The Scrum Master doesn’t work to stop Teams from trying risky things, things that might fail, but rather works with the Team to ensure that experiments are relatively safe-to-fail. A Scrum Master doesn’t just worry about keeping everyone happy, but rather challenges the Team to improve.