After this comes seeing the same preview, but with your perfectly-designed book cover. Then, the first time you hold that first printed copy in your hands. (Stroking, smelling and fondling are requisite responses here) Having someone buy the book, review it, ask you to sign it... these are all equally mind-blowing experiences from which you never descend.
I had the opportunity recently to walk my daughter, Ellie, through this process with her first book, Society's Foundlings. Today, I had the same experience with my friend, Angie Fuentes, and knew exactly the indescribable joy she was feeling when she first saw her pages on the screen before her. I'd been there, in that moment, and was so thrilled and honored to be able to be there, in that same moment, with her.
Because, that moment, right there, is why we do this.