Question: should I rate movies I didn't finish?
If I watch, say, a half-hour of a movie and I don't continue watching it because it just didn't grab me, then I think the fact that it didn't spark my interest is a good reason to give it a low rating. But on the other hand, if I kept watching it, it might've turned out to be something I really loved, so giving that movie a low rating might cause the algorithm to not recommend similar movies that I also might have really loved.
So, this is a question about how I should handle that on the website as it currently is, but it's also a suggestion/recommendation that they should add a feature where you can check a box to indicate that a rating is only based on a partial viewing of a movie, and those would then be factored differently somehow.