
Investing in the right stock at the right time can result in substantial returns. One investor managed to turn a $300,000 investment in Nvidia (NASDAQ:NVDA) into more than $20 million after a few years.
Even though it turned out well for the investor, it's risky to put all of your eggs in one basket. Financial personality Graham Stephan recently made that point and mentioned that he only invests in index funds. He then explained why he has a diversified portfolio and touted its benefits.