Blushing unseen, wasting one's sweetness

I love these two lines:

Full many a flower is born to blush unseen,
And waste its sweetness on the desert air.

They come from the much-loved poem Elegy Written in a Country Churchyard, written by Thomas Gray in 1750. The two lines state a simple truth, I think, not only about certain flowers but about many acts and deeds and even people. The point is made straightforwardly but oh, so poignantly.