Too many people approach books with an attitude of achievement and arrival. I can't count the number of discussions I've overheard that treat books as if they are the equivalent of running a marathon or summiting some famous peak - "Yeah, I've read Infinite Jest, I thought it was pretty good. "Oh, I haven't read that, but I did make it through Ulysses."
The reason I take issue with this spirit is that it reduces a wonderful art form to a sort of masochistic endeavor. I think that literature is unique among art forms in this dilemma, largely because of the effort that reading requires. With visual art, such as paintings or sculpture, all the activity that is required is to find a museum, pay for admission, and walk around with your eyes open - you can typically see an entire piece in an instant (I said see, not comprehend, calm down, artists). With music, even the avant-garde stuff that is parading as genius nowadays (what, I don't have a bias, what are you talking about), you typically are in a seat in an auditorium, and once you're there, all you need to do is stay seated, and the music will at least hit your ears, even if you don't want to hear it. With performance arts such as opera, dance, and theater, the effort may be slightly more involved in that you have to use both your eyes and ears, but again, typically, you're already in a seat in an auditorium, and unless you try to fight your way out mid-concert, you're going to witness art. With reading, though, you have a page in front of you, and you are the one that dictates the pace - your abilities as a reader impact the performance, and if your attention wanders, you aren't obliged to keep sitting there, staring at the page.