Try to do something difficult, try to do something new, try to do anything different from what other people do. And critics, naysayers, and devil's advocates always chime in. Granted, input and feedback are certainly valuable.

But only to a point.

Sometimes, paying attention to criticism--of your business, your products, your ideas, etc.--will only serve to grind away the sharp edges.

To many, "new" can make people uncomfortable. "New" can make people feel defensive. If you're right, then I must be wrong, and no one likes to be wrong.

But if you want to be different, if you want to achieve differently, the only opinion that truly matters is yours.

Take it from Mark Cuban. "When it's your baby, a lot of times it's hard not to take all the (criticism) personally. It's hard not to feel it inside of you," Cuban said. "To be a great entrepreneur, you have to be so competitive. And when you're that competitive and people are talking bad about your (company) ... it's hard not to respond."

Or Steve Jobs. "You have to trust that the dots will somehow connect in your future," Jobs said. "You have to trust in something: Your gut, destiny, life, karma, whatever. This approach has never let me down, and it has made all the difference in my life."

Or Jobs's successor, Tim Cook. "In today's environment, the world is full of cynics and you have to tune them out," Cook said. "Because if not, they become a cancer in your mind, in your thinking. And you begin thinking that you can't."

The next time someone criticizes an idea, ask how they arrived at their opinion. Look for the data behind the conclusion. Otherwise, ignore everything that isn't data--warnings, cautionary tales, and well-intentioned but poorly grounded advice--since you already know all those things anyway. Then keep in mind, analysis can only take you so far, especially since critical thinking tends to steer a decision towards conventional wisdom.

Innovative products or services are only groundbreaking in hindsight. At some point, someone believed when others did not.

Learn to apply a little selective hearing to your critics and that someone might be you.