Part of my dad's job is doing team training and helping teams be as efficient as possible. There was a manager who came in who did not like the feedback he got from his team, so he scheduled meetings to talk about how he can be better. Each team member came to tell my dad what the leader did well and where he lacked skill. Then after every team member has a chance to share with my dad, he will bring in the leader and have a meeting to talk about what the team said the leader does right and where he can be better. It's a very effective way of giving leaders feedback because the team members won't sugar-coat things since it isn't a face to face conversation with the leader.