When you've taken a certain position, or when you're deliberating a decision, what does it take to change your mind?

If you don't have a clear answer to that, then it is likely that you will remain indecisive, or continue to hold a belief in the face of evidence to the contrary, or regret the path that you set out on when faced with the first obstacle.

Knowing what it takes to change your mind will make it easier to see the course of the path you set out on, and to make more rational decisions.