As for what's driving him in his upwardly mobile career, Kutcher says, "The only way to increase the size of your comfort zone is to bet on the fact that you can do something that you've never done before and go for it. You don't want to make a fool out of yourself. You don't want to embarrass yourself. You don't want to screw up. But most of the time those obstacles that we see in our lives as giant walls that we feel like we're going to run into, they're actually just curtains. And if you run hard enough and fast enough, you just fly right through it."
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