The Dark Tower series for me. I enjoyed Stephen King as a teenager, but had never read any of the Dark Tower books until a few year ago when a friend gave me a copy of The Gunslinger. And I really enjoyed it! It's a quick read, I thought it was compelling enough to start working through the rest of the series. I made it through book 2, a little slower of a pace but I made it, book 3 was the same I feel like, maybe it dragged a little more even. By the first few chapters of book 4 , I just wasn't having fun with it any more and put it down.
I tried to read it a few years ago and it reminded me rather quickly why I don't like King. He writes like a coke addled alcoholic, because that's what he is, and it shows.
I made it to almost the end of the series and then out of nowhere it switches to the most boring flashback for an entire book. I couldn't slog through it and have never looked at the series again.