We often talk about the top 20% of men (and, to a lesser degree, women). Do we actually care that these people are better than 80% of their peers, or does it just so happen that only around 20% of the population meets the minimum qualifications we've set for dating elligibility based on ideas we have about attractiveness, financial security, personality, and social status?

Using a different example: the obesity rate is increasing in the US. As more people become overweight, does the average value for people's looks go down, or does the average value stay the same, because "a 5" is always average relative to everyone else?