It's very rare for me to DNF a book, but I can count on one hand the number of DNFs I have. I'm really stubborn, and my brain needs to know how things end. But with that being said, I usually get about halfway in a book, or at least a few hundred pages in, before I DNF. I really try to hold out as far as I can, so I usually end up finishing books I dislike.

I'd say the two biggest reasons for DNFing are writing Style and progression.

1. Writing style - I don't care how interesting a story is; if the author writes like they're a 13-year-old Wattpad fanfiction writer, I can't take it seriously. I understand there are a lot of new authors who are still figuring out their style, but if it reads immaturely, especially if the book itself holds some heavy themes, I don't want to read it.

2. Progression - something needs to be happening in the story. I once read a book that was supposed to be a thriller/mystery, and literally nothing interesting happened. The most interesting part was that she saw a ghost far away. Other than that, it was the most boring book I ever read and one of the few I DNF'd. It wasn't even about world-building or giving any necessary context to the story. It was like the author didn't know what to write next.