12. Stan O’Neal
Stan O’Neal triggered the demise of Merrill Lynch, where he was CEO for six years. He assisted with guiding the company away from their familiar business dealings of asset management and introduced collateralized debt obligations (CDOs). Merrill Lynch loaded up on over $41 billion in subprime CDOs and mortgage bonds, which would be their undoing when the market crashed in 2008. Merrill Lynch was eventually sold to Bank of America.