What makes a great leader?

According to Andreessen Horowitz (Ben Horowitz via David Jaxon):

What makes people want to follow a leader? We [Andreessen Horowitz] look for 3 key traits:

The ability to articulate the vision. Can the leader articulate a vision that’s interesting, dynamic, and compelling? More importantly, can the leader do this when things fall apart? More specifically, when the company gets to a point when it does not make objective financial sense for any employee to continue working there, will the leader be able to articulate a vision that’s compelling enough that the people stay out of curiosity?

The right kind of ambition. Truly great leaders create an environment where the employees feel that the CEO cares much more about the employees than she cares about herself. In this kind of environment, an amazing thing happens: a huge number of the employees believe that it’s their company and behave accordingly.

The ability to achieve the vision. The final leg of our leadership stool is competence, pure and simple. If I buy into the vision and believe that the leader cares about me, do I think she can actually achieve the vision? Will I follow her into the jungle with no map forward or back and trust that she will get me out of there?