Because fast output = easy money.
One of these days, I'm afraid, AI will be actually good at making entertaining stories rather than just mass produced slop and we human writers won't be needed anymore.
We might not even be needed to direct them.
Moo Principle # 526 - I've been replying to a lot of comments recently by going to youtube and copying the clickbait video title. It's fun. I might try a randomizer.