It's true that if you set out to make a colossal mess of your 401(k), no one is going to stop you. You can cash out when you quit or borrow once too often. And now there's no longer a pension sponsor taking responsibility for paying you a certain benefit no matter what; all the investment risk falls to you.
But you're about to get a lot more help if you want it. Last year's Pension Protection Act gave employers the green light to take more responsibility for their workers' retirement savings. Now an increasing number of plans will give you investment advice or even account management. And when you start a job, your plan sponsor may automatically enroll you in the 401(k), raise your contribution level each year and direct your money into diversified investments, such as life-cycle or target-date funds, unless you opt out.
All of which means that even if you never make an independent investing decision, you can nevertheless wind up with a decent portfolio.
Still, you can probably do better with just a little effort. Forstarters, you should try to save the max ($15,500 this year) rather than the 6% or so of salary that many plans set as a default level. And while target funds work well, it's not hard to design a customized mix that suits your goals and risk tolerance. Try the asset allocator to the right.
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