One third of "something" (something being Music, movies, people you know, etc.) will be great, one third will be mediocre, and one third will blow. These thirds can be broken down in the same manner. For instance:
I would consider most of the music I own and listen to to be in the top third of all music ever. Not everyone will think so but I don't care. Within that tiny collection one-third will be superior, and probably more listened to, than the other two-thirds, and so forth.
This post made me think about that.