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"I want you to think about your work life, and your family life, and decide which is important to you."

I'll never forget those words, coming at the end of a lengthy exegesis on the virtues of long hours from an old boss. It wasn't that my work wasn't good, or that I wasn't getting enough done. In fact -- not to brag or anything -- my performance was rated by that boss as stellar.

But he found it irksome that I only clocked eight to nine hours a day. He said that if I wanted to prove my dedication to the company and make more money, I'd need to work more -- never mind that there wasn't actually any more work to do. I just needed to be a body in a chair.

I thanked him for his advice and said it gave me a lot to think about. I would have quit on the spot, but the job market for liberal arts majors in Vermont was terrible at the time. I fumed, silently, and bided my time. It took me 10 months to line up a new job. And for every work day in those 10 months, I made sure my time sheet registered exactly 8 hours, down to the minute.

Overworking in America is a real problem. Half of full-time workers report working 41 or more hours per week; nearly a fifth works 60 or more hours per week! The U.S. is one of the rare places that doesn't require time off for workers, and doesn't even offer mothers paid leave when they have a baby.

This isn't the life most Americans want to be living. Seventy six percent say that family takes precedence over work, according to a 2014 Allstate/National Journal poll. Still, many Americans are willing to make sacrifices for their jobs, as you can see in this chart:


More than a quarter of workers said they've missed important family events because they couldn't get time off from work. Fifteen percent have worked opposite shifts from their spouse when they couldn't get child care, and 14 percent say they've been "punished" for time off due to illness or caring for a family member.

More to the point for employers that promote long hours, there's ample evidence that those long hours erode worker health and productivity. A 2004 Centers for Disease Control and Prevention analysis of existing research found that "overtime was associated with poorer perceived general health, increased injury rates, more illnesses, or increased mortality." That analysis found evidence of cognitive decline happening after just ("just") 9 hours of work in one day.

And a 2014 Stanford study found that after about 55 hours of work in one week, productivity gains halt completely. Any work you could do in 70 hours -- or 100 -- you could also get done in 55.

Existing on little sleep and ultra long hours is the stuff of lore in corporate America. But this conveniently overlooks the fact that those who succeed combine skill with luck. Most start-ups fail. According to Shikhar Ghosh, a senior lecturer at Harvard Business School, for every top chief executive out there who succeeded, there are 19 more who worked just as hard, but whose visions didn't happen to pan out.