Peter Principle
In a hierarchy, everyone rises to their level of incompetence.
Definition
The Peter Principle rests on an implacable logic: in a hierarchy, people are promoted because they are good at their current job. But competence in one role does not guarantee competence in the next. Promotion continues until the person is finally incompetent, and there they stay.
At the organizational scale, the result is that every position eventually ends up occupied by someone incompetent. The work is done by those who have not yet reached their level of incompetence.
Why it matters
This principle points to a structural flaw in traditional promotion systems: they reward past performance rather than future potential. An excellent developer is not necessarily a good manager. A top salesperson is not necessarily a good sales director.
It suggests alternatives: lateral promotions (expanded responsibilities without changing the nature of the role), separate technical recognition from management progression, and assessing potential before promoting.
Concrete examples
The promoted teacher: brilliant in the classroom, they prove a poor administrator as principal.
The promoted salesperson: high-performing in the field, they are paralyzed by administrative tasks and team management as sales director.
The promoted engineer: a technical expert, they have no taste for human coordination as project manager.
Expert career tracks: the creation of Staff Engineer and Principal Engineer roles in tech organizations is a direct response to the Peter Principle, keeping top performers without forcing them into management.