It's fairly difficult to determine what goes on inside any head but our own....but the way I see the answer to your question is to base it on hypothesis. IF an individual has, in fact, caused more harm than good, over a period of time and has done this all quite knowingly and intentionally.....THEY ARE SIMPLY NOT THE "TYPE" OF HUMAN BEING WHO WOULD FEEL REMORSE OR REGRET. If you're a nasty sociopath AND/ OR greedy BASTARD, (which is a reasonable assumption of one intentionally destructive)......a conscience does not exist. Therefore, they live with themselves just fine. Examples? Casey Anthony, Scott Peterson, OJ Simpson, Drew Peterson, Bernie Madoff, Dick Cheney, C.E.O.'s of Major Corporations who bilk the public..........there are hundreds of thousands living quite well and hunky-dory doing a hell of a lot more HARM than good. How? They just DON'T GIVE A DAMN ABOUT ANYONE OR ANYTHING BUT, "I, ME, MINE, MINE MINE!!"