You know when a movie plays pompous music when nothing important happens (that's unearned) or when they hail a leader that did nothing important (that's unearned) or when they start spamming cliche phrases of triumph when nothing important was achieved (that's unearned)?
Something similar happens when a game has things like follower systems to get passive rewards (it feels unearned); or when they give extremely important items from easy small dungeons (it is unearned); or when RNG plays the most important role (randomness is de facto unearned).
They should reward hard work above else; anything passive should be for pure artistic enjoyment and not unearned rewards; randomness should be kept to a minimum and not be used for excessively powerful rewards (unearned).