The chips were down

My dumbest investment was selling NVIDIA shares that I’d bought at around $16 each a decade ago, as part of my retirement account. I held them for a few years, then sold because the stock wasn’t performing — yet. I missed out on a return of 14 or 15 times my original investment of $10,000. I learned to be patient, especially when I know the company is on the right track. — D.M., online

The Fool responds: Yikes — with NVIDIA shares recently topping $500 apiece, you missed out on more than a thirtyfold gain in your investment.

But we can’t capture all of every great stock’s gains. Your job as a long-term investor is to park your hard-earned dollars in the most promising investments you find, and then to wait — often for many years, and possibly for decades. Lots of great stocks will increase in value tenfold, twentyfold or sometimes even a hundredfold over long periods. As long as the company is performing well, maintains competitive advantages, and still has plenty of room to grow, it’s best to hang on — through inevitable temporary downturns and occasional slumps.

NVIDIA, which specializes in programmable graphicsprocessor technologies, has grown powerfully, but many still expect yet more growth due to demand for its chip technology that serves high-end video gamers, data centers and even cryptocurrency miners.