Why do people struggle to develop self-confidence?

Confidence in men is attractive to women the way physical beauty in women is attractive to men. And lack of self-confidence, insecurity or shyness in men is a turn off to women the way woman ugly face turns men off.

If self-confidence in men is so attractive to women then how comes some men struggle to be confident no matter how you persuade them? People struggle to develop self-confidence because of phenomenon known as "confirmation bias". According to Cambridge dictionary confirmation bias is the fact that people are more likely to accept or notice information if it appears to support what they already believe or expect.

While dictionary.apa.org define confirmation bias as the tendency to gather evidence that confirms preexisting expectations, typically by emphasizing or pursuing supporting evidence while dismissing or failing to seek contradictory evidence.

Examples of how confirmation bias influences our perception

1. A woman who has intense fear of cats (Gatophobia) is very conscious whenever she enter her room to make sure there is no cat in the room. One day someone kept a piece of cloth on top of a chair in her room that has the same colour as cat; when the woman entered the room and saw the piece of cloth she instantly perceived that cloth as cat and from there she has a panic attack and her body start trembling only to realised what she saw is a piece of cloth not a cat.
2. Whenever a gossip rumoured that someone has some faults, chances are people will always look for any mistakes that person do as proof of those faults just to prove their sentiments while discard the fact that everyone do mistake occasionally.
3. A chamer will believe his spell or black magic work if 1 out of his 10 spell/black magic coincidentally come true while discard the fact that the remaining 9 failed to work.
4. Likewise if someone lost self-confidence based on the belief that people look down on him and regard him as dumb he will usually discard any evidence that contradict this belief and accept any evidence that supports it. So if such person passing through a people and they suddenly laugh he will have a paranoia that they are laughing at him. If people are gossiping about shy guy he will come to the conclusion that they are gossiping about him. If he meets someone who is not in a good mood and he looks down on him that will instantly prove his sentiments while discard the fact that people behave differently if they are in bad mood. If he ask a girl out but she rejected him he will concluded that she rejected him because she regarded him as dumb. Likewise if he started a relationship with a lady but she dumped him thereafter he will come to the conclusion that she dumped him because she regarded him as dumb and different.
   
   These are some of the examples why whenever someone lost self-confidence may hardly revert it back without seeking therapy because he already formed identity that he developed in his subconscious mind and attached to it over the years based on what he believes people think of him that influences how he think and behave.