I know there's a book thread floating around here somewhere, but it's early and I haven't had enough coffee, and it's very difficult to be patient with a tennis ball getting beaten into my thigh.
I'm reading a couple of sci-fi books at the moment, and a couple of things popped into my head.
Jack McDevitt cannot end a book.
The last 20 pages drift on and on, looking for a point. It eventually gets there, and his books are very readable, but I notice myself struggling to read the last few chapters every time.
David Weber has somewhat different habits.
The beginnings of his books can be tedious, but if you've read his work before, you know you have to read thoroughly, as there's a detail in there somewhere that you'll be looking for later. He also tends to get into Dickensian descriptions of tech/activities that he's familiar with. (I've accused Dickens of taking 4 pages to describe a room when only one small piece of that description is actually important)
Any odd observations on your favorite authors?