Great at Work: The Hidden Habits of Top Performers

by Morten T. Hansen

Does working long hours increase performance? The prevailing “work harder” mindset presumes that it does, but the truth is more complicated. We analyzed the relationship between weekly hours worked and performance among the 5,000 managers and employees in our study.5 As the “Squeezing the Orange” chart reveals, working longer hours enhances performance, but only to a point. If you work between 30 and 50 hours per week, adding more hours on the job lifts your performance. But once you’re working between 50 and 65 hours per week, the benefit of adding additional hours drops off. And if you’re working 65 hours or more, overall performance declines as you pile on the hours.6 Other research has documented the same inverted U. Studying factory workers at a weaponry plant in Britain in 1914, Stanford economist John Pencavel found that performance topped out at 64 to 67 hours per week, beyond which it began to fall.7 Where the curve starts to flatten and where it plateaus may vary from job to job and industry to industry. It’s like squeezing juice from an orange. At first, you get a lot of liquid. But as you continue to squeeze and your knuckles turn white, you extract a drop or two. Eventually, you reach the point where you’re squeezing as hard as you can, but producing no juice. You would have done better just to leave the well-squeezed orange alone. It’s the same with hours worked. If you’re already working 50 hours per week, resist the temptation to invest more hours at work. ...