Goodreads asked Alan Cook:

How do you deal with writer’s block?

Alan Cook I believe writer's block is fear--fear that you aren't writing your best, and fear that others won't like what you wrote. Let's take them one at a time. Writer's block is most common during the writing of the first draft of a book. Remember that the first draft is not the final draft. Writing is revising, and it is during the revision process that a book gets put in readable form. As far as readers not liking what you wrote, you can't please everybody. Strive to please yourself first, and others will like your work. Don't worry about the ones who don't.

flag