Billionaire Mark Cuban said he turned career setbacks into lessons that shaped his success as an entrepreneur. Heather Diehl/Getty Images Mark Cuban said getting fired early in life helped teach him how to become a better entrepreneur. The billionaire said jobs he hated taught him valuable lessons about leadership and business. Cuban said entrepreneurs only need to succeed once after repeated failure in business. For some workers, getting fired can feel like a career-ending setback. For billio