Successful businessman Elon Musk has said that people must work from 80 to 100 hours per week to "change the world". Mr Musk knows. He has his finger in many pies. He is the founder, CEO and lead designer of SpaceX; the co-founder of the car company Tesla; and the co-founder of PayPal. He works very hard on many projects that have changed our lives. He is a workaholic but he loves what he does. He talked about hard work in an interview with a technology news website. He said: "There are easier places to work, but nobody ever changed the world on 40 hours a week."
Workers at Mr Musk's companies also put in very long hours. He said "everyone" at Tesla has worked 100 hours per week at times this year. This was to make sure a Tesla car could survive. He said: "There wasn't some other way to do this." Musk said some Tesla employees were unhappy with their long hours. Some called the hours "excessive". Others said they prefer to work 70 or more hours per week. Musk said the "pain level" increases above 80 hours a week, but he didn't say what the pain was. The average CEO of a multi-billion-dollar company works about 70 hours a week.