It is a common fear. Some have fear of success. And either one can keep a person stuck.

It's a "what happens next" fear. That is, if I fail, then________ .. you fill in the blank for yourself, see what's there.

We truly fail all the time. We try, and sometimes things work out and sometimes they don't. We learn what we can and go on, having failed in one respect, but having gained in another because we have learned and grown.