The highest leverage work a leader can do is to focus the efforts of his/her team on a single goal or priority.
The usual analogy is of a boat where the leader's job is to get the right people in the right seats and all rowing in the same direction. However, rowing is neither fun nor inspirational.
Lately, I've been thinking more about leadership as a magnifying glass. Picture the bad kid in a movie using a magnifying glass to concentrate sunlight to start a fire or to burn ants.
The leader's job is to focus everyone's energy on a single point. The combined, focused effort of the entire team is the leader's output. With this concentrated energy, the team is better equipped to reach its goals.
If everyone's work was instead scattered and directed towards a variety of goals, the team wouldn't achieve any of them.
(Illustration from Essentialism by Greg McKeown.)