Bernard Knox said this quote

“ If through no fault of his own the hero is crushed by a bulldozer in Act II, we are not impressed. Even though life is often like this—the absconding cashier on his way to Nicaragua is killed in a collision at the airport, the prominent statesman dies of a stroke in the midst of the negotiations he has spent years to bring about, the young lovers are drowned in a boating accident the day before their marriage—such events, the warp and woof of everyday life, seem irrelevant, meaningless. They are crude, undigested, unpurged bits of reality—to draw a metaphor from the late J. Edgar Hoover, they are “raw files.” But it is the function of great art to purge and give meaning to human suffering, and so we expect that if the hero is indeed crushed by a bulldozer in Act II there will be some reason for it, and not just some reason but a good one, one which makes sense in terms of the hero’s personality and action. In fact, we expect to be shown that he is in some way responsible for what happens to him. ”