Kellerman describes the bad types of leadership in seven groups. He lists them as incompetent, rigid, intemperate, callous, corrupt, insular, and evil. “The first three types of bad leadership tend to be as in ineffective, and the last four types tend to be bad as in unethical.” (pg. 396)
I find that each of the seven are horrible styles of leadership, however, I believe if I must pick the worst I would have to say that evil would be the absolute worse. “They use pain as an instrument of power.