Saving money for retirement isn't enough. Sure, it's a stepping stone to success. But to accumulate a respectable amount of money for retirement, you need to do more than just keep building cash. You should plan to invest your money so it's able to grow over time. Remember, inflation is apt to erode the value of money over time. So you need to invest your retirement savings in a manner that can outpace it.
As a barometer of US industrial and corporate economic health, the S&P 500 Index has few equals. Over the past decade, less than 15% of professional large-cap fund managers have been able to surpass the performance of the S&P 500. In fact, no less an investing authority than Warren Buffett cited in the 2013 Berkshire Hathaway shareholder letter: " The goal of the non-professional should not be to pick winners...instead, seek to own a cross-section of businesses that in aggregate are bound to do well. An S&P 500 index fund will achieve this goal."