To me the sakura is a heartrending existence. It's beauty often celebrated, yet lasting only a short while.
It doesn't matter that the blooms will return the following year. That moment when you stood below a sakura tree in all its glory will never return.
The fleeting existence is a reminder of the importance of the significant (the memories) versus the insignificant (the surface beauty).
That may be why they say, "A perfect cherry blossom is a rare thing. You can spend your whole life looking for one, and it will not be a wasted life."
