From Sign and Sight:
Not long ago, the Norwegian Academy addressed one hundred writers from all over the world with a single question: Name the novel that you consider the best ever written.
Of the one hundred consulted, fifty answered: “Don Quixote de la Mancha” by Miguel de Cervantes Saavedra. Quite a landslide, considering the runners up: Dostoevsky, Faulkner and Garcia Marquez, in that order. The results of this consultation pose the interesting question of the long-seller versus the best-seller. There is, of course, no answer that fits all cases: Why does a bestseller sell, why does a long-seller last?
Don Quixote was a big bestseller when it first appeared in 1605, and has continued to sell ever since, whereas William Faulkner was definitively a bad seller if you compare the meager sales of “Absalom, Absalom” (1936) to those of the really big-seller of the year, Hervey Allen’s “Anthoy Adverse”, a Napoleonic saga of love, war and trade.
More here.