Because AIG was, despite its huge size, a one-man show - Greenberg's. He was kicked out in the end, but the transition was not smooth and he knew more about the company from the outside than the insiders, given that he had built it up.

Brief history:

AIG history dates back to 1919, when Cornelius Vander Starr established an insurance agency in Shanghai, China. Starr was the first Westerner in Shanghai to sell insurance to the Chinese, which he continued to do until AIG left China in early 1949--as Mao Zedong led the advance of the Communist People's Liberation Army on Shanghai. Starr then moved the company headquarters to its current home in New York City. The company went on to expand, often through subsidiaries, into other markets, including other parts of Asia, Latin America, Europe, and the Middle East.

In 1962, Starr gave management of the company's lagging U.S. holdings to Maurice R. "Hank" Greenberg, who shifted its focus from personal insurance to high-margin corporate coverage. Greenberg focused on selling insurance through independent brokers rather than agents to eliminate agent salaries. Using brokers, AIG could price insurance according to its potential return even if it suffered decreased sales of certain products for great lengths of time with very little extra expense. In 1968, Starr named Greenberg his successor. The company went public in 1969.