Doing Two Things? That's One Too Many. If you aspire to be a successful entrepreneur, the only way you're going to achieve that is by focusing on one thing and doing it better than anyone else.

Everyone has three or four careers going at once these days. The problem is nobody can keep that many balls in the air at the same time. If you don't focus on holding onto one, sooner or later you're going to drop them all.

That's fine if you don't mind slugging it out with the competitive masses and living hand to mouth on slim profits, if any. But if you aspire to be a successful entrepreneur, the only way you're going to achieve that is by focusing on one thing and doing it better than anyone else.

I was recently counseling a young software developer. He had several new business ideas but all of them had been done before. He could tell me what he wanted to do and name similar sites but he couldn't tell me how his ideas were different, how he was going to come out on top. No wonder he couldn't decide which one to focus on.

In a recent Wall Street Journal essay, venture capitalist and PayPal cofounder Peter Thiel says, "If you want to create and capture lasting value, look to build a monopoly." He says entrepreneurs should ask themselves, 'What valuable company is nobody building?' This question is harder than it looks." He's right. Most startup founders and CEOs never come up with the right answer.

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The only way to be successful is by figuring out what you're best at and focusing on just that. It's true for each and every one of us and every company no matter how big it is.

In a recent interview with Charlie Rose, Apple CEO Tim Cook said that "[striving] for being the best, for only doing the best products, for staying focused" was a core principle that Steve Jobs instilled in the company. He said he could put every product the company ships today on a small table. And Apple's sales will be about $180 billion this year.

"It's easy to add. It's hard to edit. It's hard to stay focused. And yet we know we'll only do our best work if we stay focused," he said. "And so the hardest decisions we make are all the things NOT to work on. There are lots of things we'd like to work on that we have interest in but we know what we can't do everything great."

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To further the point, Sony just surprised Wall Street with news that it will lose more than $2 billion this year. The Japanese giant's much-talked-about turnaround is once again faltering. The problem is that Sony can't excel at being a global entertainment and consumer electronics company at the same time. There are simply no synergies between the two.

Another example of companies that spread themselves too thin is Yahoo. Brad Garlinghouse, then a senior vice president at the floundering Internet company, penned an internal memo that came to be known as the Peanut Butter Manifesto wherein he tried to convince fellow Yahoos that the company lacked cohesive vision and focus, that it was trying to be too many things to too many people.

Of course he was right. Eight years and five, maybe six CEOs later (it's hard to keep track), the company is still struggling with the same problem.

As far back as I can remember I've been counseling companies and individuals to focus on what they're best at. If you're still trying to figure that out, don't let a few false starts get you down. It's a good sign that you're at least putting yourself out there. If you put all your wood behind one arrow at a time and make it count, sooner or later you will hit the bulls-eye. One thing's for sure; it's a lot smarter than learning to juggle.

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