There is a story...
A legend...
About a bird that sings just once in its life.

From the moment it leaves its nest, it searches for a thorn tree and never rests untill it's found once,
And then it sings more sweetly than any other creature on the face of the earth.

And singing...

It impales itself on the longest sharpest thorn.
But as it dies, it rises above its own agony to out-sing the lark and nightingale.

The thorn bird pays its life for just one song,
But the whole world stills to listen,
And god in his heaven smiles.

It means that the best is bought only at the cost of great pain.

The Thorn Birds