Rewatchability factors greatly in selecting my favorite movies. Flaws run rampant in many of the movies below, but when it comes to what I love, I just don't really care. There are probably about 15 movies that battle for this list; if I were to watch one of the outside five today, it may well supplant one of those listed.
I could watch any one of these movies at any moment. I don't let a year pass without revisiting them. And I even keep my physical copies separated out from the rest of my collection and displayed on a special shelf.