This is reflective of a case in New York where a bank robber went in as ‘himself’ to rob a bank. When the police asked him why he didn’t wear any disguise he said that he put lemon juice on his face, took a Polaroid picture of himself and he was nowhere in the picture, thus he concluded that lemon juice made his face disappear. Click here to read the article The Anosognosic’s Dilemma: Something’s Wrong but You’ll Never Know What It Is by Errol Morris.
A couple of psychologists got a hold of that interesting fact/story and decided to look at it from a “competency” standpoint. They have concluded that our incompetence precludes us from seeing our incompetence.
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The reverse of that is why the highest achievers among us rate themselves the poorest when it comes to self-assessing a skill. The reason is that they see where they could be and where they are and detect a major gap.
A less competent person rates themselves higher because they don’t see much of a gap between where they are and where they could be. They don’t think they can be any better than where they are.
So the next time someone asks you about a skill that’s a core skill for your success, make sure that you think about your answer and be cautious about self-0assessing too high. If you do, that may be an indication that there’s a lot of room to grow.