that's how (the way) the ball bounces/cookie crumbles

This is the way things have turned out and nothing can be done about it; that’s fate. These expressions became current in America in the mid-twentieth century and quickly spread to the rest of the English-speaking world. Both are enhanced by alliteration, and neither has a totally clear meaning. The bounce of a ball on an uneven surface can affect the outcome of a game, and a cookie disintegrating into crumbs is difficult to consume neatly. Edward Albee used the latter in his play, The Zoo Story (1960): “‘Well . . . naturally every man wants a son, but . . .’—‘But that’s the way the cookie crumbles?’”