The PeterPrinciple maintains that everyone rises to their level of incompetence. So if you can do a job you are promoted until you reach a job you cannot do. And there you remain. So the bulk of work in an organisation is done by people who have not risen to their level of incompetence. Yet.
Gotthold Lessing first described this phenomenon in 1767 when he said To become more than a sergeant? I don’t consider it. I am a good sergeant; I might easily make a bad captain, and certainly a worse general.