In his popular book, What Investors Really Want, Professor Meir Statman explains that investors want to play the investment game, and they want to win. They believe their investment advisers can help them win by picking skillful active managers.
Take a look at your 401(k) plan investment options. They are most likely predominately actively managed funds, with management fees of 1 percent or higher. Ask your adviser to justify including these funds in the plan. Don't accept the glib, patronizing response you are likely to get.