I think most people automatically understand that we value the qualities that we ourselves have. People good at math have some tendency to value others in terms of math ability. Attractive people tend to think that attractiveness is important. Kind people value kindness. Athletic people value any or all of the attributes of athleticism: strength, speed, coordination, strategy. If we are putting focus into something ourselves, we think it must be important. Wherever your treasure lies, there will you find your heart.
Here's an interesting twist, and a second. Among some of us who have a great deal of something this is completely out of control, and our valuation of artistic ability or attention to detail is not merely higher than average but swollen to pathological proportions, measuring all others primarily by the yardstick which favors us most. Yet there are a few who seem to go in the opposite direction, to humility about the arbitrariness of what they excel at and remarkable admiration for excellence in unrelated places. Sometimes this might be feigned, sometimes jealousy, but I think sometimes it is quite real, and people have hit that transcendent place analogous to Galadriel's gift to Gimli "Your hand shall flow with gold, but over you gold will have no dominion."
They also show no jealousy when someone excels them in their own endeavor, but simply rejoice. They greet such a one seamlessly as a traveling companion or a teacher. As best as I can piece together the memories over the years, these two qualities of admiring the abilities of others in both their realm and others go together, likely springing from a true humility. Humility, just to be clear, is not pretending that our skill is incompetence for show, but an accurate assessment. I don't think Larry Bird is especially humble, but he is on record saying of a few others "When he's in a game I'm watching I can't take my eyes off him. I just enjoy watching him work." No mention of where he ranks him in comparison to himself, simply admiration.
I have known only a few, and of course I do not know the inner workings of their minds and I may have been fooled. If they are only pretending to be humble and appreciative of others, we should at least be grateful that they understand that is the proper value and aspire to it. If they at least try to hold their excellence lightly, perhaps it will become true some day.
Here is the second twist: I have never seen that transcendence in those who were pretty good at something. I have seen a healthy attitude to the abilities of others - in fact, I see it often. Most of us are comfortable with "I'm good at golf; Jerry's good at dancing." Yet somehow it is harder to drop the things we remain more aspirational in, the places where we are the B+ or A- students. We keep that yardstick near the top of the pile and reach for it quicker than others. We just can't quite drop it. We see others through that lens.
Well, my personal data is necessarily limited. We will know very few people of surpassing excellence because of Gaussian distribution alone. Further biasing that sample is that we will tend to know them in our own fields, so the general application will be less visible to us. Finally, I may have this entirely wrong. I may be making it up and forcing the data into my theory just because I have known a few people with great gifts who seem to be magically humble as well.