A book by Roger V. Fulton
by that title lists 25 common mistakes made by new supervisors (Appendix III).
I chose a few to list here, not as criticisms of this forum, but as some of the more likely to apply to internet forums where ideas and egomaniacs might cross paths. I have not changed words like "subordinates" although it might not be the exact term in this situation. Among these are:
1) Made changes for the sake of change
2) Immediately made drastic changes in discipline or procedures
4) Failed to take cahrge of the department
10) Had an inconsistent approach to problems
13) Showed faboritism among subordinates
15) didn't address problems of subordinates
16) failed to make timely decisions