'He works 120 hours a week': The harsh reality of working for Tesla's Elon Musk.

For two decades now, Elon Musk has been known as one of the world’s most ambitious and hard working entrepreneurs.

The head of three major companies, electric car company Tesla, aerospace manufacturer SpaceX and brain-computer interface company Neuralink, Musk has been praised for his extraordinary work ethic time and time again.

But speaking to the New York Times last week, it’s clear things aren’t running as smoothly as they seem.

“This past year has been the most difficult and painful year of my career,” he said, tearing up throughout the interview.

“It was excruciating.”

Working hard on the production of the Tesla Model 3, Musk who is currently dating singer-songwriter Grimes missed his own birthday, spending the entire 24 hours of his 47th birthday at work.

He narrowly missed his brother’s wedding, too.

Ford & Tesla are the only 2 American car companies to avoid bankruptcy. I just got home from the factory. You think this is an option. It is not.

— Elon Musk (@elonmusk) August 19, 2018

“This has really come at the expense of seeing my kids. And seeing my friends,” he told New York Times.

For months, the father of five has been working 120 hours a week – often not leaving the factory or going outside for three or four days at a time.

He hasn’t taken a week long vacation since 2001 (when he was very sick).

When he eventually does go home, he often has to turn to Ambien or face no sleep at all – a move which some board members have attributed to Musk’s late night erratic Twitter sessions.

Earlier this month, the billionaire tweeted that he planned to take Tesla private at $420 a share – which led to a subpoena from the US Securities and Exchange Commission.

Am considering taking Tesla private at $420. Funding secured.

— Elon Musk (@elonmusk) August 7, 2018

While in July during the Thai cave rescue, the Tesla CEO infamously insulted British cave diver Vern Unsworth, calling him a “pedo” after his plan to send in a ‘kid-sized’ Tesla submarine was rejected.

But Elon Musk’s inhuman work schedule is not just taking a toll on himself – it’s taking a huge toll on his employees too.

“Elon talks about being a socialist and doing good for mankind – unless you work for them,” one source reportedly told the New York Post.

“It’s a sh*t show.”

According to another source, Musk often promises things he can’t actually deliver – and once his mind is set, it’s difficult to change his mind about the reality.

“He is very difficult to move off his stance,” one source said.

“He’ll say, ‘The car can do X, Y or Z,’ and yes, that is possible – two decades from now.”

When fans ask when a new feature will be available, Musk will often respond, offering a date when the feature will be available even when the request is outlandish or physically unrealistic.

For months, Tesla has had a string of resignations with as many as 14 people resigning in recent months – including people from some of the company’s top positions.

“Everyone realises it’s f*cked up, but everyone’s afraid of losing their job before Tesla ‘hits it big’. It’s a mess,” a source said.