Why Entrepreneurs Must Believe in Themselves Reflecting back on his life, serial inventor Stephen Key recalls the importance of having confidence. Trust yourself to make good decisions, he advises. Have the courage to make changes when things don't feel right.

I can remember sitting in a classroom at Santa Clara University and looking out of a window at the rain, feeling desperately unhappy. I didn't want to be studying economics. It wasn't that my classes were tough, although they definitely were. It just didn't feel right. This is not my future, I thought. I knew it in my bones.

So I took a chance. I took an art class. I wasn't an artist but I remember thinking that there had to be more to life than economics. This turned out to be one of the best decisions I have ever made.

Looking back, I can see that I made a lot of decisions that my friends and family didn't understand at the time. In fact, I'm not sure that anyone believed in me back then.

I'm proud that I have had the courage make changes when something didn't feel right.

One of the defining qualities of being a successful entrepreneur is the willingness to stop and re-evaluate a situation that's not working. And entrepreneurs are constantly hoping for improvement.

The truth is that I believed in myself when no one else did.

There will be so many unknowns in your career. But one thing I know for sure is that entrepreneurs must believe in themselves, especially when others don't. Own the fact that it's your life that you're living and trust yourself to make good decisions.

Here are a few of the sentiments that keep me going and help me continue believing in myself:

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1. Time heals all wounds.

This statement is a cliché, but I've found it to be true. Time gives people the perspective they need to deal with difficulties, whether they are physical scars or personal struggles. I have started thinking about failure as my friend.

If I'm failing, I'm moving forward. So I try to not let it discourage me and take solace in the fact that as time goes on, my failures will become less and less painful.

2. Anything worth achieving takes longer than one might expect.

Pride and appreciation are developed over time. That's actually a great thing. Learn to be patient. Keep moving forward and try to not become discouraged by how long it takes to create something. There are no overnight successes and you need to hang tough to be successful.

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3. I can figure out anything.

My dad taught me that the power of observation is unparalleled and that there isn't anything someone can't learn by teaching himself or herself. I may not always end up with results that are 100 percent right, but I can get close.

This belief has empowered me to try new things all my life. I know I don't have to wait for someone to give me permission. I know I don't need to become an expert to get things done.

4. The path to success is never straight.

You might as well learn to how to navigate curves since the way forward is never completely straight.

Finding my purpose in life has helped me continue to have faith in myself. I let this be my guiding light. When I become distracted, this reminds me of what's important. When things aren't going my way, I turn to my purpose for inspiration.

And when all else fails, I stop focusing on myself. I surround myself with positive people. I read books about other peoples' lives for perspective.

Don't get me wrong: I still get nervous. I still wonder whether I'm making a mistake. That feeling never goes away.

But everything else has fallen into place (like I always knew it would) because of my conviction. I found a way to live with the unknown and you should try to, as well. Your path to becoming a successful entrepreneur will be littered with failures and successes. Don't let either of them define you. It's a marathon not a sprint.

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