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Yahoo CEO Marissa Mayer
She's regularly pulled off all-nighters during her time at Google, and even worked from her hospital bed shortly after having her twin babies last year. It's why former Yahoo director Max Levchin calls her "the hardest working CEO in Silicon Valley, bar none."
Mayer says hard work is an important part of any business and an often overlooked part of Google's success. She shared more details around her 130-hour work weeks and why it matters in an interview with Bloomberg:
"The other piece that gets overlooked in the Google story is the value of hard work. When reporters write about Google, they write about it as if it was inevitable. The actual experience was more like, 'Could you work 130 hours in a week?'
"The answer is yes, if you're strategic about when you sleep, when you shower, and how often you go to the bathroom. The nap rooms at Google were there because it was safer to stay in the office than walk to your car at 3 a.m. For my first five years, I did at least one all-nighter a week, except when I was on vacation-and the vacations were few and far between."
Mayer adds that hard work is what separates the startups that succeed or not, and that she's able to tell which ones are more likely to succeed, without even knowing what they do, by simply looking at their work ethics.
"Being there on the weekend is a huge indicator of success, mostly because these companies just don't happen. They happen because of really hard work," she said in the Bloomberg interview.