Lyft CFO Brian Roberts said coasting in your career is the "kiss of death" that can be impossible to recover from in an interview with Forbes.No matter how successful you become, he said you can never afford to stop learning and growing.The harder you work, the luckier you will get, Roberts said.No matter how high you get on the ladder of success, there's always room to grow.That's true whether you're an entry-level worker or an executive at a $15 billion company, like Lyft CFO Brian Roberts.In an interview with Forbes, Roberts said it can be impossible to recover once you start coasting in your career, something he calls the "kiss of death.""You have one career. You can never afford to stop learningI always want to be growing, today even more so," Roberts told Forbes contributor Zack Friedman. "Never coast in your career.That is the kiss of death. It's nearly impossible to recover."He continued: "When opportunities emerged in my career, I was picked because management knew I was ready to assume bigger leadership roles. Change is the natural state of business, so be ready."Roberts seems to be making the most of his current position. Since becoming Lyft's CFO in 2014, he's helped the company grow 5,000% and has helped raise more than $5 billion in capital.As he climbed the ladder at companies like Lyft, Walmart, and Microsoft, Roberts said he was presented with increasingly better opportunitiesand it wasn't just luck."I joke that I'd rather be lucky than smart, and I'd be lying to you if I didn't say I caught some lucky breaks along the way," Roberts said. "But I'd also say the harder I worked, the luckier I got. I strongly believe that folks need to push and challenge themselves to be ready to do more."Roberts is far from the only successful person who claims to be a lifelong learner. Author and TED speaker Simon Sinek told Business Insider in 2016 that the best leaders are "students of leadership" and "tend to think, 'I could do better.'" Similarly, theHarvard Business Review wrote that good leaders are in "perpetual beta mode" and navigate changes in society "by being receptive and able to learn."But you don't need to be in the C-suite to learn new skills. Check out some of our favoritebooks andonline coursesto learn new business skills at any stage of your career.SEE ALSO:12 signs you're a terrible employee ' even if it doesn't feel like itDON'T MISS:Two entrepreneurs who appeared on 'Shark Tank' scored $100,000, but a piece of advice from one of the Sharks ended up being much more importantJoin the conversation about this storyNOW WATCH: One of your most important career decisions is who you have kids with Click here to read full news..