A number of the points in the top answer are really symptoms of not being aware of what is going on with your people. One of the fatal flaws (for the manager if not the company) I have observed in poor managers is a lack of spending time with the team members.
At least in tech, many managers are promoted from individual contributor roles and they only carve out a little time to be a manager. Usually that means they don't know what is going on, and when issues do come to their attention those issues have been festering for quite a while.
At least in tech, many managers are promoted from individual contributor roles and they only carve out a little time to be a manager. Usually that means they don't know what is going on, and when issues do come to their attention those issues have been festering for quite a while.