Elon Musk, CEO of SpaceX and Tesla, has earned billions for his work re-imagining the way we travel, both on earth and in space. But the business magnate didn't create these innovative companies alone.
With an estimated 4,000 employees at SpaceX and around 30,000 employees at Tesla, Musk's No. 1 tip for young leaders makes sense: "Hire great people."
Hiring talented individuals, he tells company review site Glassdoor, is "90 percent of the solution as hiring wrong can cost you so much."
He's right: Financially, it takes an average of 52 days to fill an open position, up from 48 days in 2011, according to research compiled by Glassdoor. Additionally, U.S. companies spend $4,000 on average to fill each vacant position.
Musk has a solution to filling open roles with the best employees: He sometimes conducts interviews himself. In 2015, he tweeted that he was looking for "hardcore" software engineers, who he would personally interview. he tweeted
When speaking with job candidates, Musk asks questions about problems they have solved in previous roles. The entrepreneur specifically wants to determine if the candidate solved the issue single-handedly or as part of a team.
"People who really solved the problem, they know exactly how they solved it; they know the little details," Musk says.
Choosing the right hire is key when it comes to company culture. Both SpaceX and Tesla have bold ambitions: to get humans to Mars and to power the world by battery, respectively. To accomplish these goals Musk says he pushes his leaders to seek only the brightest talent.
"We challenge our people leaders to hire people that are better than themselves," Musk tells Glassdoor, "therefore making the company better with each hire."
Though being extremely talented is important, Musk also seeks candidates with a positive attitude.
"It's very important to like the people you work with," he says, "otherwise your job is going to be quite miserable."
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