Quoted from JEFFPINS12:Pinside ratings are only there because owners trick the system and rank their own personal collection very high because they want the value to stay higher
I don't think that argument applies in most cases. There may be some of that going on, but usually people buy a particular game because they enjoy it above and beyond all the games they didn't buy. So of course they would tend to give that game high marks; otherwise they would have bought something else they liked better.