It's quite simple
, really: if you don't get caught
, no one will know that you've done anything wrong
. If you're really lucky
, or really good
, no one will ever even realize that a crime
has been committed, and then (if you take a subjective
, postmodernist view
) it's almost as if nothing
at all. Except, presumably, for some net benefit
Consider: people are only punished by society if they get caught doing something "wrong". There is the possibility that they will punish themselves with a guilty conscience, but people most often have some means of justifying their actions ("I needed the money more than he did" or "He was a fucking Commie!"). If society doesn't catch you, you haven't committed a crime -- the beauty of being innocent until proven guilty.
Not that I'm advocating any of this, of course -- it's just a sociological observation.