Having a strong work ethic and developing a reputation for being able to execute on projects is one of the most important determinants of career success, said Marc Spilker, a former Goldman Sachs exec who's now chairman of Chiron Investment Management. Working hard leads to learning more, which leads to improving, which leads to getting more opportunities, according to Spilker. Getting to see as many opportunities as possible, and then selecting the best ones, is what ultimately translates into career success, he said. You've heard it 1,000 times: 80% of success is showing up.