Caroline Alexander said this quote

Surely, by all convention, the Iliad will end here, with the triumphant return of its vindicated hero. But the Iliad is not a conventional epic, and at the very moment of its hero's greatest military triumph, Homer diverts his focus from Achilles to the epic's two most important casualties, Patroklos and Hektor: it is to the consequences of their deaths, especially to the victor, that all action of the Iliad has been inexorably leading.