There are three kinds of leadership: coercive, charismatic, and conventional.
Coercive leadership is what you get in a dictatorship, or a pack of dogs. The leader is whoever took the post by force. They stay in power as long as they can defeat or deter challengers, which requires that the leader is the strongest, literally or in the sense of being the most ruthless. There is a top-down power structure that keeps the majority in line by reminding them that they have no choice.
Charismatic leadership is what you find in a band, or other relatively fresh voluntary association. The leader is perceived as being the best at whatever is the aim of the organization. Followers follow the leader because they value their inspiration and direction. Any challengers would have to demonstrate superior ability, rather than attack the leader as such.
Conventional leadership is the kind found in democratic states and other large, mature organizations. The leader has no distinguishing characteristics other than fairness and commitment. The members of the organization subscribe to the leadership because they see the benefits of structure and coherence. The leader is expected to identify and publish a consensus direction, but not primarily to steer the group.
All three kinds of leadership have validity, including the coercive one in certain contexts. Problems in leadership typically occur when the leader misrepresents, is not true to, or changes the kind of leadership that they are in charge of.