Shark Tank star Kevin O’Leary says you’re ‘stupid’ if you work this many hours per day

Investor and Shark Tank star Kevin O’Leary once declared that to succeed in business you must be willing to grind out 25 hour work days. He has since walked back on that idea, calling it, in his own words, “sheer stupidity.” 

In fact: “The worst advice I hear young founders talk about all the time is that they want to work 18 hours a day. How stupid is that?” O’Leary said in a video posted on his Instagram page last week.

The eat-sleep-work lifestyle—also known as the “996” schedule first imported from China...