A new book about Elon Musk, written by Bloomberg technology reporter Ashlee Vance, is filled with quotes and anecdotes that provide an inside look at the entrepreneur behind Tesla, SpaceX, and PayPal.

There are several quotes that paint a picture of just how much time Musk commits to the job. One person who previously worked with Musk even said he works 23 hours a day, according to the book called “Elon Musk: Tesla, SpaceX, and the Quest for a Fantastic Future.”

Musk even scolded a Tesla employee for missing an event to witness the birth of his child, Vance’s book says.

Here’s the email Musk reportedly sent to a Tesla employee that wasn’t identified by name in the book:

That is no excuse. I am extremely disappointed. You need to figure out where your priorities are. We’re changing the world and changing history, and you either commit or you don’t.

The quote above is just one snippet from the book that illustrates how Musk prioritises his work above most other things, including his personal life.

When an employee complained in Tesla’s early days that they were working too much, Musk said he would “tell those people they will get to see their families a lot when we go bankrupt,” Ryan Popple, one of Tesla’s earliest employees and who is now CEO of electric vehicle manufacturer Proterra, told Vance for the book.

We reached out to Tesla regarding the quote above, and will update this post accordingly if we hear back.

You can read more about some of the most interesting things Musk has said in Vance’s new book over at The Washington Post.

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