I reread a lot of books a lot of times, especially ones I actually bought and enjoyed most of the ride. (We're talking ~100-200 new books a year and more that are repeats, mostly audiobook.)

The ending to the dark tower is so bad I'll probably never read it again. It's not the premise. Plenty of books have done that premise perfectly well. It's the most horrendously bad presentation of that premise that I've ever seen.

Steven King endings always feel like he just got bored and wrote whatever awful trash he could think of with no intention whatsoever, and it's even more frustrating because he has interesting ideas and makes them moderately compelling at the start. I'd say it feels like a pretty solid author just handed the last chapter to a random kid to write, but I think the kid would do a better job. He just never has any idea where he's actually going by midway through the book, and doesn't know how to end a book with "spooky" questions still in the air either.