Figure out what we are really trying to do. . . . - Eugene Rotberg

Always measure opportunities lost.”<ref>Rotberg, Eugene. (2009).

Banks are unprofitable because they make too many bad loans and their good loans have little profit in them. They also have the dubious advantage of an awful set of accounting conventions—“a rolling loan gathers no loss”—that permits them to mask their mistakes and hold assets without marking their value to market. Spreads are narrow, costs are high and there is too much reliance on insured deposits, with the accompanying incentive to take risks with someone else's money.

Ignore accounting conventions. They are not useful risk management tools; they are designed to make our lives easier and comfortable.