satya nadella milk mustache microsoftMicrosoft CEO Satya NadellaReuters-Robert Galbraith/Business Insider

Back in 2015, a weird dairy epidemic struck Microsoft office kitchens worldwide.

Employees were opening an eight-ounce carton of milk from the fridge, pouring a splash into their coffee, and leaving behind the opened container so the next person could finish it. 

But nobody wanted to use milk that might have already spoiled, so the next person would just open a fresh carton, and leave it behind.

The cycle continued. 

The Orphaned Milk Carton culture is somehow deeply ingrained in our worldwide culture,” one Microsoft employee wrote on Reddit at the time. 

In his new book, “Hit Refresh,” Microsoft CEO Satya Nadella tells the story from his perspective — and how he turned it into a teachable moment for the company as he tried to reform Microsoft’s dog-eat-dog culture

Nadella writes that the problem came to his attention when the milk carton issue blew up in an internal group on Yammer, Microsoft’s corporate social networking tool. While Nadella doesn’t mention it in the book, that group was called “Milk cartons of the Pacific Northwest,” and featured photos of lonely containers spotted around campus.

Meanwhile, a cornerstone of Nadella’s leadership style is the idea of the “growth mindset,” or the idea that you should take nothing for granted and always be willing to adjust your views as new data comes in. The opposite of a “growth mindset” is being set in your ways to a fault, what’s called a “fixed mindset.”

“[…] I used one of my video messages to employees to have a good laugh at it, showcasing it as a humorous example of a fixed mindset,” writes Nadella. 

chocolate milkMicrosoft’s milk cartons were approximately this size, before they adopted a new way of doing things.Damian Dovarganes/AP

Nadella doesn’t address the solution here, but we’ve heard that Microsoft ended up addressing the milk situation by getting rid of the tiny containers and replacing them with full-sized, quarter-gallon milk containers. Employees pour their bit of milk, and put it back in the fridge for the next person to use, until it’s gone. Problem solved.

To Nadella, this is a light-hearted example of a serious problem he inherited when he first took the reins of the company: How do you get Microsoft employees to stop fighting each other, and to start taking responsibility for improving the company?

This is something that Nadella spends much of the book addressing. He describes how he forced executives to interact with employees way below their paygrade at a luxe corporate retreat, and how he eventually had to tell his team to “stop whining” and that “to be a leader at this company, your job is to find the rose petals in a pile of shit.” 

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