In the Steven Spielberg movie E.T., why is the alien brown?
In Love Story, why do the two characters fall madly in love with each other?
In Oliver Stone's JFK, why is the President suddenly assassinated by some stranger?
In the excellent Chain Saw Massacre by Tobe Hooper, why don't we ever see the characters go to the bathroom or wash their hands like people do in real life?
Absolutely no reason.
Worse, in The Pianist by Polanski, how come this guy has to hide and live like a bum when he plays the piano so well?
Once again the answer is, no reason.
I could go on for hours with more examples. The list is endless. You probably never gave it a thought, but all great films, without exception, contain an important element of no reason.
And you know why? Because life itself is filled with no reason.
Why can't we see the air all around us?
Why are we always thinking?
Why do some people love sausages and other people hate sausages? No fucking reason.