I agree that teaching others what you know is a key ingredient for leaders. The aim should be to have your followers surpass you eventually. A second class lead

I agree that teaching others what you know is a key ingredient for leaders. The aim should be to have your followers surpass you eventually. A second class leader will try to prevent that, that's a lose-lose for everyone. Another reason that I think is missing here is when a person that should be a leader has a very liberal mindset that comes with a reluctance to tell other people what to do, regardless of ability (skill + confidence).