Mike Cohn from mountaingoatsoftware.com mailed a nice list of common agile mistakes:
Being way too ambitious in how much work was selected for the next iteration. A few people reported doing this even in the absence of management pressure to do so.
Trying to facilitate a meeting using someone else’s style. We each have our own style. Use that. Teams recognize when we’re pretending we’re someone else and facilitating with their style.
Holding meetings or other events at the wrong times. A few people reported doing sprint reviews a few days early, but then not having everything ready to demonstrate.
Telling people what to do. This seemed like a common problem, especially for any of us who worked as traditional project managers before adopting an agile approach. Other Scrum Masters reported the opposite problem, saying they remained too silent during team discussions.
Letting a story into the sprint without enough clarity about what was needed. A few people emailed that this happened because a product owner pushed for the story to be included. Others, though, said it was the team that wanted to bring the story in despite a lack of clarity.
Trying to fill every hour with planned work during sprint planning. Some teams fear an unallocated hour. When sprint planning seems done but a few people have extra hours, they planned work into those hours and then learned they’d overloaded the sprint.
Not asking enough questions. A couple of Scrum Masters said they didn’t ask enough questions. I’m pretty good at that by now, but early on, I would literally track the number of questions I asked versus the number of statements I made in each meeting to try to improve.
Forgoing the usual meetings because the team size was small. A few people replied to say they took the already-lightweight Scrum framework and lightened it further by leaving out some meetings because their teams were 2-3 people. They learned this was a mistake and that even small teams benefit from every Scrum event.
Not pushing teams a little harder at improvements they’d decided to make. In their retrospectives, some teams chose to improve at things like demonstrating to users more often or improving collaboration between coders and testers. And a few of you said you didn’t push your teams hard enough to make the improvements they’d chosen themselves.
Allowing too much discussion into the daily scrum. A few Scrum Masters and coaches emailed to say they changed the format of the daily scrum away from the standard three questions, and that didn’t work as well. Other said they let teams discuss problems too long and daily scrums started to take much longer. Another had let the daily scrum turn into a design meeting.
Not letting go of a mistake. A number of people said that they tend to replay mistakes in their heads or let mistakes gnaw at them. Once the mistake has been made, learn from it. Then let it go.