Before Elon Musk became the richest person in the world with an estimated worth of $238 billion, he used to get really angry when employees in his first company Zip2 didn’t work late, as told by one of his former colleagues in a new BBC documentary that gives us an insight to the Tesla CEO.

Former vice president of Zip2, Jim Ambras, shared his experiences on the first episode of BBC’s “The Elon Musk Show” documentary. More specifically, Ambras said that Musk would walk around the offices in late evening hours looking to see who was still working and who had left. If the entire company wasn’t still there at 9:00 pm, Musk would get so angry that “he turned red”.

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As reported by Business Insider, another former employer at Zip2, systems engineer Branded Spikes, spoke to the BBC producers about his former boss. Spikes described Elon Musk as an “unusual fellow” who worked late, slept under his desk, and seemingly knew it all. The working-late habit seems to be something that followed Musk from as early as childhood, as his mother Maye Musk confessed she would struggle to wake him up in the morning because he would stay up all night reading books.

Palo Alto-based Zip2 was a city guide software provider for newspapers founded by Elon Musk and his brother Kimbal Musk back in 1995. Compaq bought Zip2 for $307 million in 1999, with Elon getting $22 million and Kimbal another $15 million out of that deal. Musk would go on to create Paypal before selling it to eBay for $1.5 billion in 2002. In the same year, he founded the aerospace company SpaceX which is one of his current businesses alongside Tesla, Neuralink, and The Boring Company.

The documentary by BBC attempts to shed light on Elon Musk’s personality through interviews with his friends, family, colleagues, and enemies. Due to copyright issues, “The Elon Musk Show” won’t broadcast outside the UK.

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