Most of it is caused by fear they let fear and anxiety take the best part of them which make them predict about the future's of there trades, well this mostly doesn't only happen to average traders only but average business owners to are also facing this which its called the fear of successes.
Fears of success? Is this a different meaning that you make to attract the interest of discussion?
Afraid to succeed in trading if the meaning is different from the intention of fear of failure is not suitable because trade involves the loss of money if someone fails and continues to fail. But it's up to you what to do.