Uh huh!It’s fun, isn’t it? Do you find yourself cleaning up the kitchen or getting ready for bed and having a character’s conversation or plot change pop into your head?
I'm more of a re-writer than a writer. Getting the words on the page is hard. But I love to polish the sentences until they gleam!
I was in a critique group and posted a chapter with a paragraph I worked on for hours. I got a comment of "I love this," and that made my day. Week. Month.

That's priceless!My dear hubby of 54 years refers to it as a “crotch novel”.
I know what you mean about mistakes wreaking a book. I found several in one of Jeffery Deaver's books (The Bone Collector, et al). Totally pissed me off!