The word deserved can hide whether we are discussing effort, need, conduct, or luck.

The word deserved covers at least four different arguments and slides between them without notice. It can mean someone worked for it, or needs it, or behaved well, or simply that things turned out that way, and each of those supports a completely different conclusion. Disagreements about desert are often disagreements about which of these is in play.

So when the word appears, ask which sense is meant, including when you are the one using it. Say the underlying claim in plain words instead: she put in the hours, he has nothing, they kept their promise. The conversation gets slower and considerably more honest.