SARB money market operations  Central banks around the world injected significant amounts of liquidity into the money markets as they sought to avoid the worst outcomes of the crises on their respective economies. To avoid a repetition of the Great Depression, central banks acted with much flexibility, speed and urgency.
That is, regulators are compelled to act as a surrogate for market discipline since the market signals that usually accompany excessive risk-taking are substantially muted, and because the prices to banks of government deposit guarantees, or of access to the safety net more generally, do not, and probably cannot, vary sufficiently with risk to mimic market prices.