There’s a quote in The Catcher in the Rye, attributed to Wilhelm Stekel:

The mark of the immature man is that he wants to die nobly for a cause, while the mark of the mature man is that he wants to live humbly for one.

In most cases, one can do a lot more aggregate good over a long period of time than in a flashy moment, and we should live our lives in recognition of that reality.