We confuse the fact that brains can be rational with the belief that brains are always rational. Mostly we just rationalize our beliefs rather than generate rational answers.
The allure of an easier or more comfortable alternative. It's never nice being forced out of your confort zone, but like any exercise worth doing, mental or physical, you never regret it in hindsight.
According to Gino “we are trying to make a good impression on others, and show them we are knowledgeable and competent individuals.” Taking advice somehow feels like admitting that we don’t really deserve our high status.
Oh, the irony... since ignoring obvious advice only makes us look even more stupid.