Back on topic, it depends on what you mean by "retirement account."
There are:
Traditional 401k
Roth 401k
(the other variations on 401k like 403b or 459?)
Traditional IRA
Roth IRA
and Taxable investments
All of these other than Taxable investments have incentive fees (usually 10%) on at least some of the money in them to get you to leave your money in until you are at least 59 and 1/2 (though there is a loophole if you get laid off at 55 or something).
Roth IRAs are nice for 2 additional reasons:
1. You can remove your contributions (not earnings or balance transfers from traditional accounts) at any time without penalty (you put in 5k when you're 20, you can take out 5k when you're 21 or 38 or whatever with no taxes or penalties owed)
2. Money that has been transferred from a Traditional IRA to a Roth IRA can be withdrawn tax and penalty free after letting it sit for 5 years. So what some people do is transfer 30k or something per year from a Traditional IRA to a Roth IRA (and pay income taxes on the transfer but no fees). Then 5 years later they have 30k that they can withdraw tax and penalty free.
If you have a traditional 401k plan, you can transfer all of that to a traditional IRA tax and penalty free when you change jobs or quit/retire.
So the 3 step plan is:
Given: Have enough savings in either taxable accounts or Contributions to Roth IRA's to cover living expenses for 5 years, and enough in 401k to cover a 4% (or whatever) withdrawl rate for the rest of your life.
1. When you retire, transfer all of company 401k to a traditional IRA
2. Each year, transfer 1 years living expenses from the traditional IRA to a Roth IRA
3. At the end of 5 years and for each year after that, withdraw money from Roth IRA equal to what you transferred into the Roth in step 2.
Note: Dont forget 5 years of inflation when calculating how much money to transfer in step 2.
There are also SEPP payments to get money out of some of these plans, but they sound like a lot of work for <1% of your savings per year. Look them up if you're interested.