Former top executives at Moody's Investors Service testified before a Congressional panel that the firm changed its focus from providing investors to cultivating relationships with megabanks and broker-dealers whose securities it was supposed to objectively rate. Gary Witt, a professor in Temple's Fox School of Business, was a managing director in the firm's U.S. derivatives group. "The profit margins were so wide," Witt said, "and yet management really stinted on hiring staff. I didn't understand it then and I don't understand it now."