Every good leader must manage, and every good manager must lead. Still there is a difference in the concepts as a matter emphasis, and some executives become effective at management (i.e. executing on projects through people). However, this is not a complete set of leadership skills. The other side of that equation is knowing which project to execute. In some sense, a great leader is effective at two things: 1) making the right list and 2) getting it checked off.
If a leader is only capable of leading himself then it is he who does the “checking off” of the list. As leaders grow in their capacity, they’re able to engage more people or more layers of complexity in getting that list checked off. It seems as though, in my organization, there are people who can grow in their capacity to get the list checked off, but knowing which list to make (at least at the most strategic level) is a rarity.