That seems like the wrong take away to me. Why do we change our minds so little?
1.)Some of our positions are just right.
2.)We are wrong, but we don't take the time and effort to understand why we should change our minds.
We don't know which situation we are in beforehand, but if you change your mind less than you think you do, doesn't that mean you think you are often wrong? And that you are wrong about how you respond to it?
You could try to figure out what possible things would get you to change your mind, and look directly at those things, trying to fully understand whether they are or are not the way that would change things.