Thoughts about being skeptic and skepticism

Skepticism is based on the principle that knowledge is testable and that ideas and beliefs can be replaced if they are wrong.

Skeptics are people who want to make sure, that what they believe in and know is most likely that accords with reality. They like facts to be correct.

To be skeptic does not mean, that you don't want to believe in anything. On the other side if you believe in something wrong, it can be hard to accept because your emotional investments in the case. As a skeptic you will have to accept reality and not to be emotional influenced.

Why is some people skeptic and some people not ?