[W]e can say there are two competing theories:
A. Sarbanes-Oxley is bad for investors because the costs are excessive relative to the benefits, and
B. Sarbanes-Oxley is good for investors because it protects them and makes them willing to pay more for securities.
Theory B is usually used as an argument for keeping Sarbanes-Oxley Section 404 mandatory, but it is actually a great argument for making it voluntary.