Fresh out of Scrum Master training, I thought I had a pretty good handle on what the job would involve. Years, and many teams, later, the role continues to intrigue me with its nuances and layers of complexity. Here are some of the things I wish I had known when I started.

1. The techniques mentioned in the Scrum Guide can apply to Scrum, Kanban and things in between. A team can still do daily standups, retrospectives, and regular backlog refinement regardless of the agile approach being used.
2. Understanding the reasons for doing daily standups, backlog refinement, sprint planning, and retrospectives is critical in order to get value from them. Understanding prevents them from turning into empty ceremonies.
3. Team members who have a lot of experience with traditional methods may struggle with agile because they are used to being told what to do.
4. Swarming on user stories is critical and really hard to do.
5. Retrospectives are easy to do poorly and for many Scrum Masters are an afterthought. They are an essential tool  to help the team grow and self-manage, yet many Scrum Masters get stuck in the “What went well, what didn’t go well, and what improvements can we make” rut that prevents the team from reaping the benefits of meaningful discussions. Mixing up the format can yield amazing and unexpected insights.
6. Part of the Scrum Master’s job is getting the Product Owner to do their job. 
7. Story points aren’t about getting an estimate. They are about getting the team to think through a problem and solution in enough detail before starting to build it.
8. I’m not expected to have all of the answers. When in doubt, I should take the problem to the team.
9. In a twisted sense, impediments are good news. When someone brings one up in the daily standup, it means that team members are no longer suffering in silence.
10. Sprints can get messy when the realities of doing development while also maintaining production systems. Much messier than they told you in Scrum Master training. It is important to experiment with different techniques for adding unplanned, high priority work during a sprint.