Does anyone remember tennis player Anna Kournikova? She was hailed as the most beautiful tennis player in the world and through endorsements became the highest paid female athlete in the sport (maybe in any sport?) even though she never won even one tournament. She still tops the lists as "the hottest female tennis player of all time" (the men, of course, are much hotter).
http://desktop.freewallpaper4.me/preview/5406-anna-kournikova.jpg
Factoid: Anna made People Magazine's list of the 50 most beautiful people in the world in 1998 (age 16). Michelle Kwan was on the list in 2000.
I was trying to remember Kornikova's name because she occurred to me immediately as an example that it isn't always accomplishment that makes an athlete attractive (pun not intended) to corporate advertisers. It happens that YuNa is also just about Korea's best athlete, so for once the system is benefiting the person of greatest merit.