A panel of experts asked whether 401(k)s were a "failed experiment" at the 2013 NAPA/ASPPA 401(k) Summit in Las Vegas on Sunday. Despite a few disagreements on some of the particulars, the panel was largely in agreement: No, 401(k)s haven't failed, but there's always room for improvement.

Brian Graff, CEO and executive director of the American Society of Pension Professionals and Actuaries, led the panel in a discussion of what 401(k)s have done for participants and what could still be improved upon.

Kevin Crain, head of institutional retirement and benefit services for Merrill Lynch, told attendees that 401(k) plans started as a "great democracy" where the responsibility for decision making fell on individuals. Now, he said, we've moved to a "democratic paternalism" where plan sponsors are working to help people get more involved through built-in features like automatic enrollment, but as investors become more astute they can move away from the paternalistic aspects and take more control of their plans.