Great managers exploit strengths, not weaknesses, in themselves and in their people:
Weak managers feel threatened by other people's strengths.
They also revel in the discovery of weakness and regard it as something to be exploited rather than remedied.
Great managers have no truck with this destructive thinking.
They see strengths, in themselves as well as in other people, as things to be built on, and weakness as something to be accommodated, worked around and, if possible, eliminated.