The following is an excerpt from our premium Motley Fool Rule Breakers service, which provides growth-oriented investors with two high-quality stock recommendations each month. As a part of its ongoing coverage of current recommendations, Rule Breakers recently sent Lyons George to San Francisco to cover one of the world's most high profile technology conferences.

Fool of potential: Twitter's CEO
Ask David and Tom Gardner which attributes they assign to world-class companies, and you'll get a set of answers that's as unique as the brothers themselves. After all -- and as the "Motley" in The Motley Fool implies -- groupthink isn't exactly a cornerstone of Foolish investing.

But both Tom and David would have at least one answer in common:

If you're trying to find truly great businesses, look for truly great business leaders.

Think Tesla (TSLA -0.92%) CEO Elon Musk, who founded PayPal in his youth and launches rockets in his spare time. While some might argue that his highly public (and occasionally pugnacious) personality is unbecoming of a corporate steward, a quick glance at his track record suggests that his talk isn't without walk. From starting a local business-oriented web company all the way back in the 1990s to more-or-less inventing online payment as we know it to having the idea that launching rockets should be private business and then having the guts to follow through on that idea, Musk has had a hand in some of the defining technological breakthroughs of the last two decades. He's also made quite a bit of money along the way: He sold his first business, Zip2, to Compaq for a cool $307 million. Multiply that figure by five, and you get what eBay paid out for his PayPal project a few short years later.

With a curriculum vitae like that, it's no wonder we here at Rule Breakers are willing to extend Musk the benefit of the doubt when he makes seemingly impossible claims. After all, he's done the seemingly impossible before -- multiple times.

So in the spirit of recognizing that great stocks (like TSLA) come from great companies (like Tesla) run by great leaders (like Elon Musk), here's a bit of ground-level good news for anyone feeling excited about Twitter's forthcoming IPO: The world's most popular short-messaging service comes complete with a truly great leader.

Meet Dick Costolo
When Twitter's CEO Dick Costolo addressed the crowd at the Disrupt conference earlier this month, he didn't mention how much money his company is slated to make next year (about $1 billion) or what sort of valuation Wall Street is attaching to the whole kit and caboodle (about $10 billion). In fact, he barely even mentioned money at all.

Twitter CEO Dick Costolo earned a degree in computer science only to move to Chicago to pursue improvisational comedy. Image source: Author.

Instead, he made the maverick move to give a brief talk on leadership. Suffice it to say, this Fool was impressed.

In his seven-minute speech, "How to Lead," Costolo conveyed his two most important rules for any leader in any business. And while his objective was clearly to school the entrepreneurs in the audience on the importance of running their companies the right way, he also made it obvious that Twitter's exquisite business is matched with a truly beautiful culture.

If you have the time to watch the full presentation, I suggest you do so. If you don't, I'll run through the highlights now.

Rule No. 1: "As a leader, you need to care deeply about your people without worrying, or even caring, about what they think about you."
Describing this tenet as paradox that all great leaders come to embrace, Costolo explained that when it comes to managing a company, the desire to be liked "is a path to ruin."

"Lead by being forthright," he said. "The way you build trust with your team and your people is by being clear with them from day one." He warned against attempting to say the things that make everyone happy all the time, claiming that this invites a sense of dishonesty to "creep into the organization."

Rule No. 2: "Find your individual superpower."
Citing a culture of hero-worship in Silicon Valley, Costolo said that the way to success isn't to merely emulate Steve Jobs' diet or to wear a Zuckerbergian hoodie to your office, but rather to find your own unique strength and then double down on it.

"Find your individual superpower, what that is, and leverage that... and be successful in your own way."

The next great tech leader?
By doing those two things, Costolo thinks that people set themselves up to have the best chance of "being as successful as [they] can possibly be." But even if you'd rather invest your money with a CEO who gets returns rather than gives graduation speeches, consider the following: If great leaders are the key to great business, and if Dick Costolo is right about his rules, and if he's able to follow those rules at Twitter... then the market could be in for a very impressive newcomer.