The financial crisis that nearly brought down the global economy was triggered in no small part by the aggressive culture and spotty ethics within the world’s biggest banks. But after six years and countless efforts to reform finance, the banking scandals never seem to end.

The important question that doesn’t yet have a satisfying answer is why.

Why are the ethical breaches at megabanks so routine that it is hard to keep them straight? Why do banks seem to have so many scandals — and ensuing multimillion dollar legal settlements — compared with other large companies like retailers, airlines or manufacturers?

Some of the world’s leading bank regulators are trying to figure that out. And they have taken to sounding like parents who have grown increasingly exasperated at teenage children who keep wrecking the family car.

This week, it was the turn of Mark Carney, the governor of the Bank of England. The latest British banking scandal was enough to make Mr. Carney, a former Goldman Sachs investment banker, sound like an Occupy Wall Street populist.