When we compare ourselves to others, we often end up comparing our secret shames to their public victories. There is no winning such comparisons, only feelings of inadequacy.
When we openly compare others, at least one of them will feel sadness about the comparison.
When we compare our in-group to our out-group, we often end up comparing the out-group's worst examples to our in-group's best intentions. This leads to fear, anger, and hate.
In any case, comparison robs someone of joy.