#9a: Leading with and leading without authority.
Compared to leading with authority, leading without authority is a stronger form of leadership. Since there is no explicit social contract or threat of punishment, followers choose freely to follow and hence follow more fervently.
(This is a simplification, which ignores the complexity of any social relationship and its inherent power structures. However, even as a simplification it functions as a useful mental model.)
Leading with authority, then, can be said in general to attract more followers but with weaker bonds than leadership without authority. That's not to say possessing authority in itself weakens a leader. Rather, since they acquire "leadership" through having been granted power, they are not necessarily required to possess as many of the traits that define a leader. The barrier for entry is lower; some may possess strong leadership qualities, but not all.