According to a report from Electrek, Musk told the workers to stopphoning in or they would quit.

Samuel Nissim, who claims to be a shareholder in the electric-car maker, shared two emails that show that the CEO told the executives to come into the office for 40 hours a week. In one of the emails, Musk said he would assume that staff had resigned if they continued to work remotely.

Nissim and Musk didn't reply to the request for comment. Insider was unable to confirm the authenticity of the emails that were posted.

The richest man in the world responded to a question from a user about how he would respond to people who consider in-person work to be antiquated.

They should pretend to work somewhere else.

Musk's first email was titled "remote work is no longer acceptble" and appeared to address it only to a listserv for executive staff.

The billionaire said that he would have to approve exceptions to the new policy in the case of exceptional contributors.

The follow-up email was sent by Musk later that day. The CEO emphasized the importance of factory workers being able to see senior staff working alongside them, according to an email.

The more senior you are, the more visible you must be. If I hadn't done that,Tesla would have gone bankrupt.

Musk said on the Recode Decode show that he sometimes slept on the floor of the factory that he worked at. The CEO said later that he scaled back to 80 to 90-hour work weeks.

The billionaire dislikes the American work ethic. In May, Musk told The Financial Times that Americans are trying to avoid going to work, whereas Chinese workers won't even leave the factory.

The comments came after it was revealed that workers at the factory in China were sleeping on the floor due to the company trying to restart production. The workers will work in the closed-loop system until June 10, according to a report.

Musk said last month that stay-at- home measures had tricked people into thinking they don't need to work hard.

According to Insider, three economists said remote work had little impact on workers ability to get stuff done and may have even increased productivity.

Tech companies are hesitant to bring workers back into the office. After the company announced that employees could work from home forever, Brian Chesky called the office an "anachronistic form" from a pre-digital age.

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