This nicely captures the interplay of tradition and innovation in the development of art forms:

'In her recent book about the novel (Thirteen Ways of Looking at the Novel), Jane Smiley points out that while the writer gets to make the rules for his or her work, the reader has the option to read it or not, and is free to "object or disagree." This critical pact has required novelists since Boccaccio to think about the best ways to lure the reader into reading (for it remains true, with few exceptions, that novelists want their books to be read). They experiment with ways of telling stories, and because some experiments are more fruitful than others, a collective wisdom eventually accrues about how to proceed.' (Diane Johnson, "The Malibu Decameron," New York Review of Books, April 26, 2007)

This may refer to fiction, but it can also apply to poetry: those who radically assert the necessity of innovative forms (along with a rejection of traditional forms) fail to consider that the traditional forms are the results of fruitful experimentation—which is exactly what the ideological traditionalists also forget!

(The article is only available in full to subscribers to the NYRB electronic archive, but this is the first paragraph, which anyone can read!)