When you think about some of the most successful CEOs, it's natural to wonder how they have time for it all. Warren Buffett allegedly reads as many as 500 pages per day.

Steve Jobs founded Apple and turned it into the biggest company in the world, but he also turned a $5 million purchase called Pixar into a $7.2 billion company as CEO.

Elon Musk is the CEO of Tesla and SpaceX simultaneously.

How can they possibly get all that done with the same 24 hours that the rest of us have each day? According to Warren Buffett, it all comes down to one small thing:

The difference between successful people and really successful people is that really successful people say no to almost everything.

You read that right

How could saying no get you more of anything? More revenue, more clients, more opportunities? These things require you to say yes, right?

Wrong. Saying no eliminates distractions and allows you to focus on the things that matter most. And it's anything but easy.

Jobs said no to a college degree after just six months. Our society labels that a questionable choice at best, and he admitted in his commencement speech to Stanford's 2005 graduating class, "It was pretty scary at the time."

Nonetheless, he pointed out that the decision allowed him to focus on the things that he was passionate about, saying, "The minute I dropped out, I could stop taking the required classes that didn't interest me, and begin dropping in on the ones that looked far more interesting."

For Jobs, that meant saying no to a degree and saying yes to Reed College's renowned calligraphy program. It's a trade most people -- excepting calligraphy fanatics -- would be loath to make, but he credited it with the success of one of his most popular products.

"Ten years later," Jobs said, "when we were designing the first Macintosh computer, it all came back to me. And we designed it all into the Mac. It was the first computer with beautiful typography."

Start saying no

As Jobs famously pointed out, "I'm actually as proud of the things we haven't done as the things I have done. Innovation is saying no to 1,000 things."

As you finish out the year and think about next year's strategy, it's not too late to adopt this powerful mantra. When you juggle too many projects and responsibilities, you're liable to end up dropping them all.

Spend time making a list of the top 10 priorities in your life.

Now remove the bottom seven.

That's where you say yes going forward.