" Low-quality mortgages ended up imperiling the entire financial system—not so much because of the direct losses on the mortgages themselves, which were significant but likely manageable, but because of the securitization boom, which carved those mortgages into securities that became a ubiquitous form of currency and collateral throughout the system. "

― Ben S. Bernanke , First Responders: Inside the U.S. Strategy for Fighting the 2007-2009 Global Financial Crisis