When I open youtube, 10 of the 12 videos displayed are ones I've already watched. 1 is a live steam, and one is from a channel I subscribe to. The non-viewed vi

When I open youtube, 10 of the 12 videos displayed are ones I've already watched. 1 is a live steam, and one is from a channel I subscribe to. The non-viewed video is recommended to me frequently, but I've never had any interest in clicking on it. What possible "system" could they be using to come up with this being the best 12 videos to show me? FWIW: I pay for youtube music, which comes with youtube premium included so I don't get ads, but the recommendation system is pretty much useless.