“The Peter Principle is the observation that if people are good at doing their jobs they will be promoted. It follows that eventually everyone will be doing a job that they are not good at (otherwise they would have been promoted).”

[The book is wonderful even though it’s quite long in the tooth now]

https://www.abebooks.co.uk/servlet/SearchResults?sts=t&cm_sp=SearchF-_-home-_-Results&an=&tn=the+peter+principle&kn=&isbn=

Chris