Answer:
A young man wants to have it, but when he has it he no longer wants it. Blade in hand he attacks it And does his best to remove it. Yet he knows that it is all in vain.
What goes through a door but never goes in and never comes out?
What goes trough your head but you forget it like 3 days after?
Without this, H2O would just be 2O
Very helpful if you intend to go gently down a river.
It is something you will never see again.