you would have a different reason from one person to another.
hmm..just a thought .i think one person cheats for his benefit . It is but normal for one to desire not to fail and not lose. So, maybe he cheats coz he can't meet his goal by merely doing his best. Because, he knows his best isn't enough.
To me is all about the person and the stakes. If a million dollars was on the line and you had an opertunity to cheat would you? Some people cheat naturaly or that's how they grew up. I'll admit I cheat on some things but not important things. I don't cheat on viedo games till I beat it myself. Cheating will not improve you. Some will some won't.