on Jane Friedman site:
You have a Great Idea for a story. You are so infatuated with this Great Idea that you gush to your friends and fellow writers, “I’m going to write a book about [insert your Great Idea here]!” Your Great Idea takes up residence in your psyche. It settles in, as entitled and undisciplined as lesser royalty. Weeks pass, then months, but nothing gets written. Your Great Idea begins to pace the shag carpet of your mind.
“What’s the holdup, hon?” your Great Idea asks. “These shoes are killing me.”
“I just need a little more time,” you tell your Great Idea. “I’m not sure how to get started.”