Dr. Laurence Peter, a Canadian-born teacher and doctorate in education proposed the ‘Peter Principle’ while he was researching on teacher competence. He co-authored a book with the same title with Raymond Hull, and sold 7 million copies.
According to Dr. Laurence Peter, in a hierarchy, every employee tends to rise to his level of incompetence. As an employee is promoted based on his/her performance in the current job, he/she may not be competent to perform in the post he is promoted to. Dr. Peter based the principle on his own experience when he was promoted as an administrator to do budgets, a post he was not competent enough as he was a competent teacher.