The backbone of all music.
Adorno’s argues that all popular music is standardised in a manner that stifles the ability to create songs (or pieces of music) that are different to each other. I would argue a song in itself it only a subset of music, and in turn what makes a song a song is it’s structure and in general a song has to follow a certain structure, or it becomes something that isn’t a song.
I would almost liken a song to a poem. While a poem can be structured in a multitude of ways, I would say that a song can be as well, but what a song can’t do is disregard structure. While you can argue that a song can only be structured in a few ways (and you would probably be right), it’s not necessarily a bad thing.
I also think it comes down to the fact that audiences don’t like things that they perceive as different. I mean look at bands like The Mars Volta, I’ve got a lot of friends who don’t listen to them because they say they are too “out there”. And that perception is probably a bit unfounded, take a look at most of their songs and they sill follow a relatively simple verse-chorus form, it’s just that they’re warped to allow for improv. In the end to please the listener it has to be structured in a way that allows for familiarity.
I can’t think of too many bands that totally disregard structure, Sunn O))) being one, and I think it comes down to the fact that (rather ironically) experimental music can be too easy to replicate and potentially sounds same-y.
I entirely agree with the fact that some (there are a few that break some rules, you occasionally hear songs that start with a chorus, say) pop songs sound too constructed and there is no form of experiment of the structure of a song. But in saying that people will always try things that are different because there is always a new trend that people like better at one point or another.