81% of people want to write a book. That means, if you go to dinner with 10 other people, 8 of them have daydreamed (perhaps frequently) about seeing their name on a book cover.
So why don’t they write one?
The average book is 60,000 words. When you know what you want to say, it’s easy enough to write 1,000 words/hour.
Organize your thoughts for 30 minutes before you write and that’s 1.5 hours a day. You can also plan while you're taking a shower, driving, cooking, eating, cleaning, exercising, etc.
You could write a substantive, first draft of a book in two months – rather than spending years fantasizing about it.