The thing is, I really admire The Shawshank Redemption, it's a great film. If I was asked my opinion of the film by somebody who hadn't seen it and was considering doing so, I would be very quick to highly recommend the film to them... however, I would never put it in my top ten for one simple reason, it's not hugely rewatchable. It's the kind of film where the first time you see it the film really draws you in, the second time however I feel the film just doesn't retain that same hold over the viewer anymore. It just doesn't have that same wonder about it, and after a few multiple viewings of it (over say a few months) the film just becomes tiresome. It is a drama after all.
I base my top 10 favourites on many factors, but one of the main things being how rewatchable it is. All of the films in my top ten are the kind of films that to me A) I watch alot and B) Never get sick of watching no matter how many times I do.