Retirement funds are usually left alone for a long time, or that's the goal. In fact, the ones registered with the government provide a substantial penalty if you withdraw your funds. You may receive a tax savings when you deposit your money in a registered account but the government is prepared to delay receiving the taxation revenue until the day you withdraw them, maybe in your retirement years . . . or maybe not. The theory usually touted is that your income will be less at retirement and therefore your tax bracket will be lower. The result? You'll pay less income tax on the funds.
That's generally the way saving for retirement is sold. Does it always work that way? Some of the funds you withdraw are immediately withheld from Canadian registered retirement funds; how much depends on the amount withdrawn. From $5001 to $15,000, twenty percent is withheld. Anything over $15,000 withdrawn means that thirty percent funds will be withheld. So, in other words, if you need $20,000 be prepared to withdraw considerably more. The bank will likely also charge a few hundred to let you have the money. You may think you should receive interest on the money being held by the government. ( Why are they doing that anyway? Are they afraid you won't be able to pay the taxes owing when April 30th comes around?) Even though a year may elapse from the time you take out your own money from your retirement account until the day of reckoning when your taxes are due, you will not receive any interest on those funds. (Americans have their own, different, penalties)
Even the venerable Mr. Money Moustache suggests that retiring couples whose children are grown can be very comfortable with $40,000 a year. This amount isn't ideal because it is about $10,000 more than your pension so will require savings/investments that toss off that amount each year. It will also place you in an income bracket that will limit the benefits that might otherwise accrue to you: cheaper bus and ferry rates, medical premiums, user fees, etc. But owning your home and vehicle (or doing without the vehicle) will reduce the annual income required by that amount easily.
I was gratified to read this article in The Financial Post echoing my advice about not saving too much. Remember to have some fun and enjoy life. "A large estate may come with a list of missed opportunities."