For some of these there is a count for how many votes there are, this is a suggestion to allow caching based on that vote count to prevent large libraries from spamming the various providers every time there's an update.

My suggestion would be an option like to say "if you obtained a rating within this time then don't refresh", and to say "for every 1k votes for the rating delay the refresh by (duration)" - so something like LoTR with 2m votes on imdb wouldn't try to update the rating for a time, while a new release is still adding votes and is likely to change more drastically.