I think a lot has to do with how far the average person's standards have fallen. If you're in the top 10% or so with most skills you're probably pretty damn good at whatever it is. But with a lot of physical things these days you can be in the top 10% or even top 5% and still be pretty mediocre. I mean current estimates have the amount of americans who aren't fat, work out on a regular basis, have a healthy diet, don't smoke or drink to excess and have kept that up for a few years at under 5%.  When failure is the norm, mediocrity can seem borderline miraculous in comparison. It's only when you actually start comparing yourself to the best of the best rather than the average that you start to get a more realistic idea of what excellence in that area really looks like.