Keep your friends for friendship, but work with the skilled and competent.
— Robert Greene

Being competent means the ability to control and operate the things in the environment and the environment itself.
— L. Ron Hubbard

If this work seems so threatening, this is because it isn't simply eccentric or strange, but competent, rigorously argued, and carrying conviction.
— Jacques Derrida

The differences between a competent person and an incompetent person are demonstrated in his environment (surroundings).
— L. Ron Hubbard

A competent and self-confident person is incapable of jealousy in anything. Jealousy is invariably a symptom of neurotic insecurity.
— Lazarus Long