Repetition in the arts may well be the repurposing of a separate cognitive function evolutionarily installed to enhance survival. I’m thinking of Robert Zajonc’s “mere exposure“ phenomenon proposed by the social psychologist in 1968. That seems to be the origin of the link between repetition and pleasure. Consequently, artists, co-opting it for their own purposes, are able to add pleasure to their Works the way a MasterChef might add spices to a recipe.