Isn’t that so by definition?’ Average’ is normal and in order. ‘Above and below average’ is abnormal, and disordered.

Besides, no one is above average in all of their characteristics. If one trait is above average in a person, another one (most likely its counterpart) is proportionally below. Adding all characteristics up always sums to a 100% of ‘capacity,’ except if there is some damage present.
Does that make any sense?