Daniel J. Levitin spiega perché troviamo noiosi i caanti di Natale (e perché la musica classica in sottofondo ci fa spendere di più):

But if evolution is so smart, why do holiday carols become annoying? When we like a piece of music, it has to balance predictability with surprise, familiarity with novelty. Our brains become bored if we know exactly what is coming next, and frustrated if we have no idea where the song is taking us. […] the best music offers surprises with each new listening.

[WSJ.com]