Average looking? It's kinda like the question, of understanding the word, or the description "perfect". There isn't anything within the equation of average looking. It's what looks good... What looks good to one person, may not look good to another. Everyone has there made up look of someone there attracted to.
I recently went out on a few dates with someone I thought I'd never be attracted to, and I came to realize that it's not about the looks so much, but what it's on the inside that counts. We as human beings create this illusion of what looks good... or "average looking", or even the perfect person". I don't think there is any real answer to it. It's what is, and what looks good, and most importantly who that person is.
It means most people wouldn't be embarressed to be seen with them, not extraordinary to swing them in either direction. They are the people on the street you glance at and forget when the next person walks by