Fear of Failing
The "fear of failing" is a frequent and tragic barrier to real achievement that counselors observe in both young persons and adults.
Sadly, the more important the project or subject is to the person, the more formidable becomes the "fear of failure barrier" -- until many become blocked completely and drop out or back away. The fear can be a prison.
To attack it you need first to be aware of it, then consider how sensitive you are to criticism. Many highly creative persons "uncensor" themselves until they get a job done, and leave the judging to a trusted friend or family member.