That's because one of the most common mistakes most people make is failing to take advantage of compound interest, Robbins said in an interview with personal finance site Grow. Time is an advantage you can never get back.
To illustrate this point, Robbins gives the example of two friends who start investing the same amount a year apart from each other:
Take someone who invests eight years till he's 27 and invests a total of $28,800, or $300 a month, and then just leaves it there—doesn't add another penny. He'll have nearly 2 million when he retires at 65 if the market continues to compound like it has (at 10 percent or more annually on average).
If his buddy doesn't start till he's 28 and he invests $300 a month, he'll have invested $140,000 by the time he retires at 65. But his compounding returns will end up at almost $300,000 less than his friend.
As Robbins points out, the friend who is just one year older will be "investing longer and more" and yet still "end up with less."
One of the simplest ways to start investing is to begin contributing to your employer's 401(k) plan, a tax-advantaged retirement savings account, or to other retirement savings accounts, such as a Roth IRA or traditional IRA.
Especially when you're young, contribute as much of your income as you can and get in the habit of increasingly your contributions regularly. If you set up your accounts to add to your savings automatically, you won't be able to talk yourself out of setting aside a larger chunk.
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Video by Mary Stevens