The tendency for people to reach erroneous conclusions, but their incompetence robs them of the ability to see it.
The phenomenon was demonstrated in a series of experiments performed by Justin Kruger and David Dunning, both of Cornell University. Their results were published in the Journal of Personality and Social Psychology in December 1999. The duo concluded the following:
• Incompetent people overestimate their level of skill.
• Incompetent people fail to recognize genuine skill in others.
• Incompetent people don't recognize the extremity of their inadequacy.
• If they can be trained to substantially improve their own skill level, these people can recognize and talk about their previous lack of skill.
The Peter Principle spotlights the fact that every organisation feels the overpowering compulsion to promote a person from one level in the hierarchy to the next higher level. The danger of this predilection is that often this is from a level of competence to a level of incompetence. Thus, a competent mechanic is promoted to become an incompetent foreman, a competent foreman is made into an incompetent superintendent, a competent teacher is made into an incompetent vice-principal and a competent soldier is promoted to become an incompetent Field Marshal. In all these cases, the employees had been promoted to a position that they were incompetent to fill. Or, in other words, they have been promoted from a position of competence to a position of incompetence.