> It takes more than just misaligned incentives to get a banking crisis -- you have to have structural corruption preventing the transfer of the loss gradient back to the "misaligned" decision makers.
Nah, you can do it just on the basis of information asymmetries.
Banks can sell mortgages. People think buying mortgages is safe, because banks don't loan money to people they don't think can pay it back, and even if they did, the mortgage is backed by the house so in the worst case you can foreclose and get back your principal. So lots of people buy mortgages.
Then banks figure out that it's easy to sell mortgages, and that if they sell them it doesn't matter that much if the people they loan the money to can pay it back. Plus, the less creditworthy people pay higher interest rates, and you can still foreclose if they default. So banks make a lot of loans to people who can't afford them, and then sell the mortgages, and people still buy them.
Except that if this happens at scale, the people taking out mortgages they can't afford bid up the price of houses. And then when they start to default and you want to foreclose, you'd have to sell the house to get back the money, which at scale means that the prices would go back down to where they were before they got bid up, which means you wouldn't even recover your principal.
If everybody realizes that this is what's going to happen then people wouldn't buy bad mortgages from banks and then banks wouldn't issue them. But if enough people don't notice until after the bubble is inflated...