A lot of contemporary books I don't read twice unless they really moved me a certain way or if I favor the author. Classics I found after a few years (Jane Eyre, Villette, Les Miserables, etc.) I needed to re-read them because I forgot entire sections of the story. As I read I remembered the end mostly but the journey through it was enjoyable. Even more so because my mind wasn't filled with the wandering thoughts about how it was going to end, what happens to the characters, will I like it, etc.