There were many problems in the first days. Many people bought too many shares and then sold at the wrong time. Or they stayed in cash out of fear, and they couldn't even keep up with inflation.
"We put everything in your hands and say we want you to be an asset allocation expert and perhaps an economist," said Jerome Clark, portfolio manager for the target date of T. Rowe Price. "People just don't have the experience or the time."
The target date funds are supposed to solve those problems. Fund managers bring the experience, and you only need time to name the amount you are saving and your retirement year (or a 529 plan that uses the funds on the date your child will start college, after the required sabbatical year) .
Fund managers create an asset allocation of stocks, bonds, cash and sometimes real estate or commodities or other investments. Then, they decide what fraction of their money should be in each one, and make sure it stays that way while the markets spin. Finally, those proportions change as you get closer, or get closer, to retirement or withdrawal of tuition money.
$ 1 billion! How did that happen?
It was automatic, really.
One of the many known failures of the 401 (k) experiment is this: in the early years, putting money in a 401 (k) was an option. We still don't know how many people will run out of money in the 2040s because they didn't save enough in the 1980s, but there will be some.
To prevent more people from running out of money, many employers and the companies that help them have devised several strategies. First, enroll everyone. Second, increase the amount you save, say, one percentage point each year. Workers can stop any of these things, but most do not.
Then, the default value: instead of putting people in low-risk investments, channel their savings into funds with target dates that correlate with their age. Once the federal government blessed this measure, assets flooded the funds.