What is it that can push us to consume media we’ve already experienced before?
For some stories, going through them a second time may help you see new things. Their worldbuilding so intricate, their narratives so convoluted, there’s bound to be plenty of little things you missed on first pass. And if there’s a twist ending, some grand reveal that puts everything in a different light, you can now go back and experience it all from a new point of view.
Even if the story itself doesn’t have high replay value, maybe the thing in its entirety still evokes a special feeling you seek to recapture. A certain sense of excitement, hope, depression. Whatever it is, it hit you hard enough the first time to latch onto you, and pull you back in so much later.
It wouldn’t be surprising though if another big reason is to simply just sit down and let things into your brain without actually processing them. You’ve seen it all before, you know exactly where it’s going. There’s a weird kind of comfort to be found in that, familiarity.
Overall though, at the very least it wasn’t boring enough to put you off it forever.