We Fools don't always agree (hardly ever, really), so when a group of us attempted to pull together a list of our favorite CEOs, it was no surprise that we didn't all agree with each other's choices. But we did find that some of the same names kept surfacing, and we realized that although we didn't agree on who the great leaders were, we could agree on what made a leader great. And then we stumbled upon the one trait that no one could argue.

Let's take a look at what the members of our roundtable had to say.

Carl Hendley: Great CEOs say no to heroin
When asked why he doesn't raise prices a modest 3% on Costco's (Nasdaq: COST) 55 million customers, CEO Jim Sinegal responded, "It's like heroin: You do a little and you want a little bit more." It's little wonder that 87% of members renew.

Costco's employees are sticking around, too. With wages averaging $18 an hour and health benefits for nearly all, Costco boasts the lowest employee turnover in the industry, which keeps its labor costs lower than its rivals.

All of this focus on customers and employees is great, but what about shareholders? A picture is worth a thousand words.

It's a simple formula, really -- take equal care of your customers, employees, and shareholders, and stay off the smack, and you become the model for excellent stewardship and profitable long-term thinking in an increasingly short-term society.

Molly McCluskey: And yes to a double shot of caffeinated passion (with whip)
Since Starbucks (Nasdaq: SBUX) CEO Howard Schultz returned to lead the saucy siren in 2009, the stock price has gone on a tear. With a P/E of 27, Starbucks does look expensive compared with rival Caribou Coffee (Nasdaq: CBOU), which has a P/E of 8, but it still looks cheap next to Green Mountain Coffee Roasters (Nasdaq: GMCR),with its P/E of 32, down from 89 earlier in the year.

Since its first dividend in April 2010, the company has paid out quarterly, increasing from $0.10 to $0.13. It continues to perform strongly against other dividend-paying coffee stocks. Sure, Schultz's Starbucks memoir, Onward, reads like a self-serving lovefest, but you can't question the man's passion, his role in revolutionizing how we drink coffee, or his ability to sustain a thriving gourmet brand in a tough economy.

Rob Runett: Relentless innovation doesn't hurt, either
Jeff Bezos of Amazon.com (Nasdaq: AMZN) is a leader who relentlessly innovates and disintermediates other businesses at every turn, and still manages to store a few tricks up his sleeve. Bezos has reshaped not only retailing (online and off), but media, publishing, and entertainment as well.

Does anyone still think of Amazon as an online bookstore? Since those quaint early days, it's become the first -- and, in some cases, only -- shopping destination for millions of consumers. The product categories are nearly limitless thanks to affiliate relationships with partner sites and individual sellers. Amazon exceeds expectations in pricing, customer service, and variety, and its line of Kindle products encourages even stronger purchase patterns and shopper loyalty. The advances in its video-streaming service, tied to the Amazon Prime shipping program, will pry customers away from floundering Netflix.

Jim Mueller: And an ability to learn from mistakes
Despite his missteps this year, I still like Netflix (Nasdaq: NFLX) CEO Reed Hastings. Recognizing the bad move Qwikster would have been (separating and renaming the DVD-by-mail business), he quickly backtracked rather than bulling ahead, convinced that he was right. He also stood by his guns in maintaining the unpopular price increase as the right move for the company. No CEO is perfect, but good CEOs recognize when they are wrong and correct the mistake.

But the one thing they all have in common is ...
Although each of these CEOs leads a little differently, they all have one thing in common: They're all founders of the companies they currently lead. Think that matters? David and Tom Gardner are fans of the founder-entrepreneur, believing they bring a unique fire to companies they start. That fire is increasingly rare; the average tenure of a CEO is currently five years or less.

We don't all agree on who's a good CEO, but we all agree on what makes a CEO great -- the ability to balance shareholder interests with customer satisfaction, a personal drive to see the company succeed, a fearlessness to try new things, and the ability to rebound if those new things flop.

Of course, staying off the heroin doesn't hurt, either.

The one CEO we didn't name
There are several CEOs we didn't mention, but one former founder/CEO in particular is noticeably absent: Bill Gates. We Fools all agree that there's a serious threat to Microsoft that Gates missed the boat on. We tell you what it is in our special free report, "Two Words Bill Gates Doesn't Want You to Hear." Download a copy today; it's free for Fools.

Want to know whether we're right or wrong about these CEOs' ability to keep their companies successful long-term? Add these companies to My Watchlist.

Think we missed a great CEO? Let us know in the comments section, or tweet @MollyEMcCluskey with the hashtag "No. greatceo."