Stage 1: Dreaming
You have a brilliant idea. Soon characters and scenes fill the perfect movie theater of your mind. You want to write this novel right now. It is so much better than the drivel on which you are currently working.
Stage 2: Planning
You cover your wall with index cards. You build entire worlds in OneNote. You create complicated character maps. Yes, there are few plot holes, some inconsistencies here and there, but isn't that why we write? To break new ground? To discover whatever social or moral dilemma it is that our subconscious minds are trying to work out?
Stage 3: Beginning
You write that first scene and, hey, you know what? Not bad, my friend. Not bad at all.
Stage 4: Doubting
You are 20K in, and those characters and scenes that you saw so clearly in the perfect movie theater of your mind are starting to look like Golem in the harsh black and white of the written word.
Stage 5: Despairing
You are 40K in, and this book is complete shit. You buy a Chocolate Creme Donut and a large coffee with cream at Dunkin Donuts.
Stage 6: Hating
You are somewhere in the 50K to 70K range, and you now give zero fucks about this book or these assholes who call themselves characters. Make it end. Just make it end. You post brooding Poldark gifs on Twitter. Because Poldark.
Stage 7: Dreaming, Reprise
You have an idea for a new book, and it is soooooo much better than this drivel you are turning out right now. You stay the course, loathing your uncooperative wip with a white heat.
Stage 8: Finishing
You type "THE END." You stare at the words in stunned wonder, followed by elation. You perform a highly embarrassing dance of victory in your living room, and you don't care because YOU. WROTE. A. BOOK.