system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: Why do we prefer music that is familiar, whereas we (generally) prefer books and movies that are new?
gpt
The enjoyment of music tends to come from anticipation and deliverance, so your favourite part of the song is a rewarding experience. Having that build up and build up in your memory can make the sensation more powerful rather than less. 

A lot of the joy in a book or movie comes from the surprise of the story, and a lot of the details in it will be most enjoyable when you experience it for the first time.