It can be for a multitude of reasons; it's a thematically dense film and multiple viewings are required to understand it or it's just endlessly entertaining regardless if you've seen the twist multiple times. Pulp Fiction has always been a film I could rewatch because of its sharp irreverent writing and grimy raunchy situations the characters find themselves in. More recently, I've found Blade Runner 2049 to be a film I just can't be bored with. I've seen it at least three or four times now, and I can easily see it for a fifth time and still want to see it for a sixth time. I really connect with this movie's existential themes about what makes us human, and I still find the three way to be as enthralling as when I first saw it.