How do you measure Scrum Master performance sensibly?
Scrum Master performance is not measured sensibly with a single KPI, but with a combination of delivery metrics, team health, retrospective effectiveness, action tracking, and qualitative observations.
What is important is that the numbers are not used as a control instrument. They should serve as a starting point for conversation: Where is the team losing focus? Which blockers keep recurring? Which actions really lead to better collaboration?
More context can be found here: Scrum Master performance KPIs