Well, you're assuming she was pushed in 'to a corner where they need to make an ultimatim [sic]'. All I know is that she used an ultimatum to challenge/corner her manager, and he decided to discontinue their working relationship.

She certainly felt that she was pushed into a corner where she had to make an ultimatim. As a manager, it's my job to make sure my people don't get into situations where they feel that threatened.

I disagree with your premise. I abide by Andy Grove's philosophy, which is that the manager's job is to optimize value production by a team. Sometimes the manager's objectives are in conflict with those of the subordinates, and there is no way to avoid the problem.

A leader is not a friend or an ally, they are just a leader; the leader can be friendly and supportive, but they are still just a leader.