The Official Story is that the mess happened because of predatory lending -> poor and ordinary folk. Loan terms that they couldn't repay.
The truth back then: no need to go into that.
The truth now is that the bankers SHOULD try and figure out what measuring stick the regulators are using. Then they come up with their own mapping from real life to the regulators' measuring stick. We the customer should expect that if we are good credit risks, etc., that we will have a tougher-than-them time getting approved for a loan and pay higher-than-we-deserve interest and fees, to balance out the losses that the banks will endure on protected-class customers.
You may play "The World Turned Upside Down." http://www.youtube.com/watch?v=wSExogKSOy