There are different types of retirement plans. The most common are an Individual Retirement Account (IRA), a 401k which is usually provided by your employer, a Roth IRA (a variation of the IRA) and others. There are different advantages for each one.
The IRA and 401k are similar in that you contribute before taxes and you pay them when you withdraw the money starting at 70.5 years old (mandatory withdrawal). By then your tax bracket will most likely be lower, so you pay less taxes.
For the ROTH IRA, you fund it after you pay the taxes. There is no mandatory distribution at age 70.5 but you have to wait five years before you can use the money without a tax penalty. (not recommended to use the money until you retire).
With these changes made to the 401k plan, most of the disadvantages of the plan disappear and the money saved is made easier to be used before retirement, for certain specific circumstances.
Please read the full article as it did appear in the Wall Street Journal
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