The Peter Principle

Someone is excellent at their job, so the organization promotes them.

Then it happens again.

Eventually, they arrive in a role requiring completely different skills from the ones that made them successful in the first place.

That is the Peter Principle:

People are often promoted based on success in one role until they reach a role they are not prepared to do well.

A strong teacher is not automatically a strong administrator. A great salesperson is not automatically a great manager. Technical expertise does not automatically create leadership ability.

Promotion should not only reward past performance.

It should prepare someone for the work that comes next.

A bigger title is a strange prize when nobody teaches you how to do the new job.