I was listening to some young ladies discuss their progression through the emotional intimacies of relationships. In most cases, there's a desire to arrive a deeply unique bond or some kind... let's call it 100%. Generally, the difficulty that appears to be faced by such young ladies is the inability to build such a bond.
If I think then about myself, to find a point of reference, I find that in intimate relationships, as with many of my other interests... I'm not interested in arriving at the 99th percentile of intimacy if it requires reaching into the 99th percentile of effort. Doing 99% and achieving 99% just sounds like mediocre value. I have tended to prefer deals where I can achieve 80% absolute value for 20% of absolute effort. This is just like going to a college where a B+ is the institution's GPA, and aiming for a B+ personal GPA... because it would free up the rest of my time to get non-graded (read: more important) work done.
I suppose more broadly, it is convenient to identify oneself with a unique position within a particular category. It is less convenient to identify oneself with the intersection of multiple subsets across multiple categories. Interdisciplinary work is often like that - but that's no secret to inter-disciplinarians.
Perhaps the definition of success laid out by such types, is to achieve excellence in the discipline of moderation.
In terms of opportunity costs, one then acquires certain mastery of the relationships between the 79th percentile of more subjects than can be achieved by anyone who focuses on the 99th percentile of any single subject.