The famous author Frank Herbert took six years to write "Dune" and won the Nebula and Hugo awards the same year for it. He was paid $7,500.00. It was a science fiction/fantasy with a religious allegory.
His children and his grandchildren finally saw an income from it but the author, like Moses, did not see the promised land while he yet was alive.
We are either meant to write or not meant to write. It is up to the author first, then the publisher, to make sure the book is the best it can be to present it to the public.
The money should not be a factor. If you want to make money then do that like other people and stay on a full-time job. If you do make money with your work that only proves you have earned the praise of some men. It still doesn't prove you earned any praise from God unless the work glorifies him in some way.