Music is just layered simple patterns and our brains LOVE IT.
Sound is pressure waves, musical notes are a specific pattern of pressure waves. Melodies are repeated musical notes. Songs are repeated melodies following standard structure.
Our brains love trying to decode and parse all these overlapping patterns.
Maybe not really a shower thought and more wild speculation.
Jazz has patterns and repetition, like any interesting music genre. If it didn’t, it’d be called noise. They just aren’t as in your face and predictable as the ones employed by pop genres.