I never believed in leagues until I liked a girl that friends warned me about being out of my league (this was about 4 years ago). That was a painful experience, not because of "leagues" as such. It happened because we're such different people, we thought in different ways, did different stuff, had different priorties- basically it wouldn't have worked.
"Leagues" for me now, means different personalities. If a girl is out of my "league", for example, is stupidly good-looking, it is not because she's so hot, but because her priority is her looks, which is not something I like. A girl can very easily be in my league and be good-looking as well, its just that it wouldn't be her main focus.
Am I making sense here?