The majority of people believe that they are better-than-average. This is also called the illusory superiority. A specific form of illusory superiority is Dunning–Kruger’s effect which states that people overestimate their abilities based on their real abilities. The rule is that the less competent a person is, the more they overestimate themselves. And, on the other hand, able people have a tendency to underestimate themselves slightly.
Ask me to rate myself - in anything - in terms of basically anything, and I'll be convinced I'm above average. (Even though I'm clearly not.). Has it happened to you? How many times did you really believed that you are below average and still went ahead and scored yourself above average?
Granted, a little confidence is a good thing, as long as that self-belief is based on actual achievements, actual experiences, and actual results. Belief based on evidence is confidence.
Belief based on nothing but belief is arrogance . Alas, arrogance is infectious.
We all know situations when we met somebody who did not realize how stupid he or she is. In an internet discussion you have met a scribbler who strongly held their opinion and did not change it even after somebody had disproved it in a relevant way. After a few drinks a homely family gathering had changed into a socio-political-economic debate . You suddenly realize that your uncle is not a IT guy, but a political science professor, and that your grandmother knows more about economics than an acknowledged expert. Or rather, both of them were convinced about that.
From time to time, you hear a debate in a restaurant table next to you, and you immediately understand what the real case is with the democracy. And it must have happened to you that a friend wrote to you about incredible proof of extraterrestrial creatures and civilizations, or about an alien conspiracy he or she had uncovered. Or your friend advised you to get rid of your microwave oven because he/she had read about its harmful effects on the internet.
I remember a personal incident when I experienced arrogance rather than confidence because it was based on only belief and was not substantiated with evidence. So I was working on a project and let's call this person – X . So X comes to me and tells me to work on a project framework based on an idea that X had. With very little information, I start working and collect every information that I can. The skeletal idea now had some muscle on it and it did look better than the skeletal. Now X again comes up and tells me , put some makeup on the muscle, add little bit of technological foundation, feature lipstick and eyeshadow and make it look good. Put some unrealistic features on it so that people are wowed when they hear about the idea. Well I did bit more work and made the idea, implementation and execution process believable. I was relieved, but X uttered – “If I worked on this, I would get rid of the muscle and keep only the makeup on the skeletal, which simply meant confuse your audience with the features so much that they don’t care about the idea and what they want”. Can you guess what my answer was ? Well, I said , "That’s great but I really don’t know how to do it, It would be a critically important learning exercise for me if you could do it and I can see you doing it". Guess what happened next??? X replied , "Gargi , Your work looks great too, let's continue with what you have prepared."
Bertrand Russell wrote a warning: “The trouble with the world is that the stupid are cocksure and the intelligent full of doubt.”
Not accepting the fact that there is scope for improvement , scope for learning does not add any material to your talent, all it does is make you hallucinated frog who believes that the whole world is within the well . A hallucinated frog creates numerous supporting stories to prove that the world inside the well is the best place for the rest of the frogs. Remember the real smart people are constantly revising their understanding, reconsidering a problem they thought they had already solved. They are open to new points of view, new information, new ideas, contradictions, and challenges to their own way of thinking.
The more willing you are to entertain the possibility you might be wrong, the better choices you tend to make. And the less likely you are to "infect" the people around you with the kind of unreasonable overconfidence that leads to making uninformed and unwise decisions.