There are many qualities to be a good leader, but one important aspect of effective leadership is continuous learning and willingness to work on themselves.
Because at times, they need to face their fears and challenge their own thinking in order to arrive at difficult decisions. As leaders, they need to stick their neck out, set a compelling vision, be accountable, and should remain fearless, so that they can face opposition to their ideas.
Some people perceive that it is good enough to direct and motivate their team to do things. While knowing how to motivate others is indeed helpful, but it is of greater value if you as a leader, is willing to experience outside of your comfort zone for the purpose of learning new perspectives.
This results in exploring new ideas, seeking feedback and learning from your own mistakes. This is what qualifies you to lead others, to do the same.