Employees get promoted until they reach a job they're bad at

Laurence J. Peter argued that competent workers keep getting promoted precisely because they're good at their current job — until they land in a role that exceeds their ability, where they then stay. His tongue-in-cheek conclusion: every post in a hierarchy tends to be filled by someone incompetent at it.

— Laurence J. Peter & Raymond Hull, The Peter Principle — William Morrow, 1969
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