It's always the case where there are tons of things to do and few people are good at doing them and the rest are good at managing them. One who manages task and people well are considered to be a good leader.
Leadership comes with experience and most of the time the tough task is to manage people and no actual work. The biggest challenge we may face is that everyone has their own working style and the way they work is completely different, this may lead to a conflict of interest which further results in spillover of work.
Leadership is often considered to be a difficult task where you are bound to be under pressure and deal with lots of management tasks such as time management, people management, and resources management.
Simply, looking at the leader working on it, we feel that he doesn't do much, however, he has most of the tasks to deal with.