I doubt the possibility of being caught and punished is even considered when contemplating criminal activity.
In this case, I'm not so sure. In many similar cases, the perps got a slap on the wrist from the SEC, paid some fines, and were left to play another day. Matt and his associates were no doubt aware of this. What they didn't take into account was that the game has changed. Starting with the Enron and Worldcom scandals, financial peculation began to be taken far more seriously. Top that off with Madoff, and no one can any longer count on that slap on the wrist and an admonition not to do it again.