Lower profitability has become a fact of life for banks. What is less well understood is the extent to which this might make them more appealing to a wider array of investors. That sounds counterintuitive. But some investors argue that less can be more, especially if the reduced returns make banks more dependable and less risky.

Before the financial crisis, investment banks regularly posted returns on equity - a common measure of profitability in which net income is calculated as a percentage of shareholder equity - above 20% and sometimes even 30%. By the end of last year, the industry was operating in the 10% to 13% range, according to the Boston Consulting Group.