Obviously, you have to finish a book you write, in order to Publish a book you write! You need to write a book, for three reasons: 1. So that those who are looking for what you have to offer, will be able to find what they are looking for! 2. To show those who have always said, “You need to write a book” in order to stop you from preaching at them, that you have now written a book! 3. For authenticity, To show you are qualified to speak and teach your specific niche. I suppose at this point, I should say there are four reasons, the fourth being, 4. To prove to yourself that you believe in your beliefs enough, that you are willing to put into print those beliefs, for all the world to view.