Once every four years, most of the planet turns its attention to the soccer pitch for an unrivaled sporting pageant: the World Cup. And while Motley Fool co-founder David Gardner is not a superfan when it comes to futbol, he's a lover of sport in general, so it should come as little surprise that he, like billions of people around the globe, has his mind on the competition. But, at the Fool, our ongoing competition is to help you beat the market, so whatever he's doing, he's liable at some point to try to imagine it through an investor's lens.

In this segment, he notes that the teams that tend to win World Cups aren't usually shockers -- they are among the favorites, because they consistently deliver excellence. So, too, in the stock market: Instead of "buy low sell high," he says, "buy high, and try not to sell." Allow him to explain why that works.

A full transcript follows the video.

This video was recorded on June 20, 2018.

David Gardner: Observation No. 3. Another thing I love about the World Cup is, let's go with the word Excellence. I love that excellence is rewarded. Most of the time, the team that plays better wins the game. Ask yourself, who's playing on those teams? Generally, the most excellent players that each country can muster. I like excellence in sportsmanship outside of the actual scores of the game, and so often, we see that. I think this is just as instructive for us, again, in investing and in business.

I've often said -- in fact, one of my legacy lines, down the road -- is this: "I try to find excellence, buy excellence, and add to excellence over time. I sell mediocrity. That's how I invest." That's how I hope you invest. I think, being in pursuit of excellence in all areas of your life should be a lifelong endeavor.

Let me be very clear: in a world where many people think buy-low-sell-high is the proper way to invest, and I guess it has them looking for things that have been hit or near 52-week lows or things that don't seem to be going so well, we've done better by reversing that old axiom. I like to say, instead of buy-low-sell-high, how about this? Buy high and try not to sell. When you're buying high, what that means is, you're buying stocks that have already done really well. And guess what? They usually keep doing well if the factors in place that have led them to be excellent are real, if they're not flash-in-the-pan companies.

Being in constant pursuit of excellence, finding the best companies of our time, and you and I getting our money invested in them, we hope earlier, ahead of the mainstream, and then, especially -- this is a key to Rule Breaker Investing -- we keep holding well past when the mainstream and Wall Street have typically sold. We're trying to find excellence, buy excellence, and add to excellence over time. We're going to sell mediocrity. That's how we invest.

Just to glide over briefly to the business realm where I think about excellence, here's a thought for you. You may have heard -- I guess I'm full of old saws this week -- this old saw. It's talking about hiring for companies. Here's the line, maybe you've heard it, maybe you've used it: As hire As, while Bs hire Cs, and Cs hire Ds.

What's that's conveying is, the A players at a company typically can be expected, when they're making hiring decisions, when they're in their job interviews with multiple candidates, the As at your company are looking for other people who are awesome, because they know how important that is. They're pretty awesome themselves in the first place, so they know what awesome looks like. As hire As.

Whereas, Bs, B players, these are still good employees at your company -- presumably. I sure hope they are. I generally liked getting a B when I got one in college. I didn't take umbrage that I hadn't gotten an A. Bs, though, because they're not As, sometimes they may either lack a view into what is awesome; or, a slightly darker side of human nature, they want to hire people who won't look quite as good as they are, or might be subservient to them in some way. So, Bs hire Cs. And guess what? Cs hire Ds.

The focus, I think -- and this is something we've done at The Motley Fool for years now, feel free to swipe a page from our playbook if you're not already doing this -- I think you should have your As doing your hiring. That even means, if you're hiring a techie, maybe it's not just all techies interviewing that techie. Maybe there are people from other teams that are A players, and you're making sure they're in there doing some of the hiring decisions even outside of their own team. As hire As. Again, a focus on excellence. I think that's something that's so on display when we watch the World Cup or the Olympics together.