Bill Ackman sold his Valeant Pharmaceuticals ($VRX) stake on Monday, losing his investors more than $3 billion in the process.

Ackman had invested in the pharmaceutical company in 2015 and passionately defended them when they were accused of unfair pricing and dodgy accounting. He later took up a role on the board and helped to usher out the company’s CEO, Michael Pearson.

Looking at it now, it’s easy to suggest that Ackman held on for pride and not wanting to be proved wrong. But it’s also possible that he genuinely believed in the company and his ability to turn it around.

We can learn from him not to be so sure about one investment or not to hold on to a losing position for too long and so on and so forth. But here’s the thing – he is probably going to be all right. His reputation has been hard hit, but he will probably shake that off in the coming years. He may lose some investors, but he’ll still have plenty.

And that is the real lesson. That’s why I recently said for the rich, investing can be just a game. Losing over $3 billion is just a few years of underperformance for people like Ackman. The average investor probably cannot afford seeing his/her investment move from $150/per share to $250 and now to $12. It will be devastating. And that is why when one is investing, one must not look to the flashy, rock star style of the big fund managers. Stick with what you know – government securities, mutual funds (since Ghana doesn’t have index funds), pension funds, money market funds, fixed deposits and so on.

If you do want to go trading and stock-picking, then be sure it is not a significant part of your portfolio. Because I know for sure no one reading this can afford to lose $3 billion.