Most People Are Actually Below Average

Reach back into the deep recesses of your mind and recall the bell curve from that statistics class.
That Gaussian distribution is what most people think when they measure human performance (be it a school test or athletic performance). The bell curve posits that most of us are average, with a few extremely good and a few extremely bad people.
It turns out, however, that is wrong: most of us are actually well below average:

The bell curve powerfully shapes how we think of human performance: If lots of students or employees happen to show up as extreme outliers — they're either very good or very bad — we assume they must represent a skewed sample, because only a few people in a truly random sample are supposed to be outliers.
New research suggests, however, that rather than describe how humans perform, the bell curve may actually be constraining how people perform. Minus such constraints, a new paper argues, lots of people are actually outliers.
Human performance, by this account, does not often fit the bell curve or what scientists call a normal distribution. Rather, it is more likely to fit what scientists call a power distribution.

NPR's Morning Edition explains here.