What we learn is that if we say "yes, I was wrong", others have then jumped on us, made fun of us or made an example of us - this starts when we're kids, or in school, where if we happen to be around teachers or parents with an inferiority complex, we've quickly learnt that it's better to be absolutely right or say nothing rather than be a little wrong.

Had an interesting experience once - I have a reputation among friends for refusing to concede anything in arguments. I was debating something with a friend, and she said something I hadn't considered, to which I responded: "Oh, really? Okay, I change my mind."

Her response?: "Wow...that wasn't nearly as satisfying as I thought it would be."

Felt good.

/bragging

Moral of the story: The "winning-losing" social dynamic of admitting you were wrong is subverted if the other person perceives that you were not emotionally invested in your opinion...which is signaled by changing your mind quickly after the mind-changing argument or information is presented, and giving positive affect cues upon mind-change (similar to what you'd give after seeing the solution to a math problem).