When you act out of fear, your fears come true.
Fears about artmaking fall into two families: fears about yourself, and fears about your reception by others… fears about yourself prevent you from doing your best work, while fears about your reception by others prevent you from doing your own work.
The fear that you are only pretending to do art is the (readily predictable) consequence of doubting your own artistic credentials.
Fear that you are not a real artists caused you to undervalue your work. p. 23, 24