MATT LEVINE

The basic theory of bank regulation is that, left to their own devices, bankers would make banks too risky, so regulators and supervisors are there to make banks more boring. A bank is, roughly, a big pot of assets bought with depositors’ money; the bank owns essentially an option on those assets. If the assets go up, the bank gets a highly leveraged return; if the assets go down, the losses are largely the depositors’ (or the taxpayers’) problem. “Heads I win, tails you lose” … So banks have incentives to buy high-risk, high-return assets with as much leverage as possible, and risk-based capital regulation and prudential bank supervision counteract those incentives. The bankers — who own stock in their banks and get paid bonuses for making money — push for more risk and more volatility, and the bank supervisors push back.

The basic theory of bank regulation is that, left to their own devices, bankers would make banks too risky, so regulators and supervisors are there to make banks more boring. A bank is, roughly, a big pot of assets bought with depositors’ money; the bank owns essentially an option on those assets. If the assets go up, the bank gets a highly leveraged return; if the assets go down, the losses are largely the depositors’ (or the taxpayers’) problem. “Heads I win, tails you lose” … So banks have incentives to buy high-risk, high-return assets with as much leverage as possible, and risk-based capital regulation and prudential bank supervision counteract those incentives. The bankers — who own stock in their banks and get paid bonuses for making money — push for more risk and more volatility, and the bank supervisors push back.