[keithpeter]

"The unskilled therefore suffer from illusory superiority, rating their ability as above average, much higher than it actually is, while the highly skilled underrate their own abilities, suffering from illusory inferiority."

Dunning-Kruger effect, and it is the same in most professions where 'performance' can be a subjective judgement. Teaching, definitely!

http://en.wikipedia.org/wiki/Dunning%E2%80%93Kruger_effect

[sp332]

And Impostor Syndrome http://en.wikipedia.org/wiki/Impostor_syndrome

[rfergie]

The Dunning Kruger effect is talked about a lot on here.

More recent research casts doubt on their original study. I first heard about this on [Overcoming Bias] where they talk about a 2006 study which showed "on difficult tasks, where there is a negative bias, the worst performers are the most accurate"

[Overcoming Bias]: http://www.overcomingbias.com/2008/11/all-are-unaware.html