Fear of success is far more dangerous than fear of failure, because the subconscious mind works to prevent that which it fears. People may fear success because of low self-esteem and feeling of not deserving it; because it will increase what others expect of them. Fear of success shows up as anxiety, indecision, avoidance, procrastination or acceptance of mediocrity.
Joe Tye (2000). “Personal Best: 1001 Great Ideas for Achieving Success in Your Career”, Mjf Books