We asked entrepreneurs to share their biggest lessons of 2013, and they overwhelmed us with responses. Here are some of the best ones. “The most important lesson of 2013: Force yourself to be uncomfortable, then learn to love that feeling. No one great ever stayed within their comfort zone.” – Konrad Billetz, founder and CEO of Frameri “It’s impossible to know with certainty which stone you’ll find your next opportunity under; so don’t waste time trying to make a prediction when you already could have started working to turn one over!” – Matt Crumrine, founder and CEO of Atmospheir “It’s really easy to get stuck in a work rut when it comes to your environment. Desks absolutely kill creativity – so does boxing yourself inside the same four walls every day. If you’re experiencing work fatigue, think big about shaking up your surroundings.” – Chris Barrett, founder of PRserve “Learn to appreciate that you’ll never have a dull moment. Framing your crazy schedule and the ups and downs of startups in this light really keeps things in perspective. I’m grateful I’m not working a boring corporate job, and I get the opportunity to work every day with great people to defy the odds of building a great product with limited resources.” – Kate Doerksen, cofounder and CEO of DITTO “I remember a boss and mentor of mine telling me that the death of any business isn’t the lack of ideas; it’s the lack of execution. Focus on the most important thing first. There aren’t 10 important things. There is just one. Execute on one thing then move onto the next. It sometimes feels exciting (and necessary) to try to do everything, but it’s really easy to get bogged down.” – Jason Vitug and Max Martinez, cofounders of Phroogal “Invest, invest, invest in your product. It’s the only sustainable way to win in fiercely competitive, new online marketplaces. Hold back on sales, hold back on marketing, keep a lean business team…and spend as much time, money, and sweat as you can to maximize your user experience. Happy users will tell others and your sales problem will solve itself.” – Rob Biederman, cofounder of HourlyNerd “The biggest lesson I’ve learned in 2013 is to always stay true to your own truth and at no time underestimate your own talents. It is important not to second-guess your thoughts or feelings when running a business.” – Parisnicole Payton, director of The PNP Agency “Never give up. When you are building something new, you will want to quit as often as you find yourself floating on cloud nine. If you really believe in your idea, then work through the successes and pains the same way. With a positive, uplifting, and excited attitude. Your next sale or opportunity might be the next conversation you have.” – Michael J. Brankin, chief finder of Hansen Advertising Network “Business does not have to be so serious. You must lead with an open heart. There is a way to be kind and show just how intelligent and resourceful you are without having to don the traditional suit and tie.” – Kelly Ann Gonzales, founder and editor-in-chief of Alpha Female Society