6 Little-Known Characteristics of Successful Entrepreneurs Who could have guessed that 'introvert' is one of them?

The world of entrepreneurship is surprising. Once you enter it, you either love it or hate it. You're either addicted or turned off. You realize you can go further than you ever thought possible and work harder than you thought you were able.

Related: 12 Signs You Have an Entrepreneurial Mindset

Some of the most surprising things I've discovered have been the traits of other successful entrepreneurs. For all the "traits of a successful entrepreneur" articles you've probably read, you might easily overlook some of the most fascinating and curious traits of all.

Here are some of the surprising characteristics I've identified in most successful entrepreneurs.

1. They are self-taught.

You might think that the rock-star entrepreneurs have a leg up on the rest of us. Maybe they had a wise mentor, a powerful group of advisors or some other advantage.

In reality, many of the most successful entrepreneurs are self-taught. Take Bill Gates, for example. Slate has described him as an "autodidact, someone compelled to learn for himself what he needed to know."

Elon Musk is another example. Musk is one of the world's leading authorities on rocket science. How nerdy of an expertise is that? Musk's science degrees from Wharton and UPenn didn't furnish all that knowledge. How else did he learn it? According to Business Insider, "He committed textbooks to memory."

If you're facing down the prospect of entrepreneurship, don't let lack of knowledge intimidate you. You can learn everything you need to know.

2. They live frugally.

We've all heard the rags-to-riches stories of famous entrepreneurs, read about their stunning yachts and seen pictures of their exotic cars.

The fact is, most entrepreneurs live rather frugal lives. Forget the boss cars. Mark Zuckerberg famously cruised around in his remarkably unglamorous Acura, a car that most college grads can own. Jeff Bezos has a net worth of $46.7 billion; his 1996 Honda Accord is worth about $4,000. We're not even sure if Travis Kalanick has a car. He might be carpooling, Uber style.

Mark Cuban shares this advice on the frugal entrepreneur's lifestyle:

It doesn't matter where you live. It doesn't matter how you live. It doesn't matter what car you drive. It doesn't matter what kind of clothes you wear.

Lest Cuban sound like some preacher of austerity, look no further than his net worth of $3 billion to let you know otherwise. Cuban knows, however, that

The cheaper you can live, the greater your options.

3. They have worked menial jobs.

Jan Koum was sweeping floors, giving his earnings to his ailing mother and living off government food aid. His ascent to stardom began in a little village in Ukraine, in a house without electricity or modern amenities. Now, Koum, cofounder of Whatsapp, sits atop a net worth of $7.9 billion.

Related: 9 'Mindsets' You Need to Switch From Employee to Entrepreneur

Cuban, for his part was just a bartender at first, washing dishes and earning paltry wages. Warren Buffett sold newspapers. Michael Bloomberg was a parking lot attendant. Oprah Winfrey worked the cash register at a little grocery store. Jeff Bezos was a ranch hand. You get the idea.

Can't quit your day job yet? Don't sweat it. You're in good company.

4. They give back.

At some point, lots of money or no, entrepreneurs realize something very important. It's not about the money.

It's about doing something that matters. It's about investing in a cause greater than yourself. It's about giving to causes that matter.

• Bill Gates could have continued to build a software empire but started a giving foundation instead.
• Entrepreneur Jason Wolfe, founder of GiftCards.com, takes mission trips to Haiti, and gives Christmas gifts to needy children.
• Mark Zuckerberg plans to give away 99 percent of his Facebook shares.

It's not just about the taxes. It's about a life well lived, and an improved life for others.

5. They pursue happiness.

Much of today's entrepreneurial advice revolves around "Follow your passion" and "Do what makes you happy." But, honestly, you're going to have to do some things that don't energize or enlighten you.

On the other hand, you want to choose a life's work that gives you joy. Otherwise, what's the point?

Serial entrepreneur Philippe Courtot, a Business Insider Most Powerful Person, understands the importance of this point:

If I had one piece of advice to give my younger self, it would be to stop doing what makes you unhappy and focus on what makes you truly happy.

At some point, you're going to look back on your life. If you've spent all your time pursuing the head-banging labor that you hate, you're going to regret it.

Even if the money doesn't follow, you can at least do something that you truly enjoy, which is something that money can't buy.

6. They are introverts.

The prototypical entrepreneur is an extrovert -- a true back-slapping, deal-making, big-selling, fast-talking, energy-inspiring, high-fiving Type A. Or not.

Some of the most successful entrepreneurs are textbook examples of introverts. On this list of powerful introvert entrepreneurs, The Wall Street Journal places Bill Gates, Steve Wozniak, Larry Page, Mark Zuckerberg, Marissa Mayer and Warren Buffett.

Sounds like a who's who of entrepreneurs list. And they're introverts?

How does that work, exactly? The leading luminary of introvert science, Susan Cain, explains that their entrepreneurial prowess comes from their uncanny focus. They intentionally step out of the limelight and into the zone where they are most productive and thoughtful, and can move forward most rapidly.

As Gary Vaynerchuk wrote:

We are in the glory days of the introverted entrepreneur. Because of technology, there are so many ways to build a company now, talk to people and make connections in the business world, all without leaving your desk.

So, yes, introverts are great entrepreneurs.

Conclusion

You may not think of yourself as the "prototypical" entrepreneur, and that's okay.

In reality, there's no such thing as a "prototypical" entrepreneur. There are simply entrepreneurs. They may look weird, different, attractive, uninspiring or downright shocking.

Binding them all together is that entrepreneurial drive and can't-shake-it passion. Simply put, we're going to build things, go places and make stuff happen.

What are some of the surprising things you've discovered about successful entrepreneurs?

Related: The 5 Components of the Mindset That Will Let You Live Your Dream Life