However, he says, Musk proved him wrong by following this "single simple formula" for success: Doing what he's passionate about, doing what he's talented at and doing something that has market value.
Cantrell, who has years of experience advising billionaires and other tech companies, recalls how he first began working with Musk. The billionaire contacted him in 2001, he writes, but Musk didn't know anything about rockets or space exploration. But what he did know was that he was "deeply passionate" about it.
"He was so passionate about the need to 'make humanity a multi-planetary species' that he was willing to spend a very large portion of his fortune on it," says Cantrell.
But Musk was also business-savvy and knew that he needed rockets to launch probes into space. That would require money, Cantrell explains.
"To prolong his money supply, he needed to buy the cheapest rockets available," he writes. So Musk looked into Russian launch vehicles, which he was interested in purchasing.
However, once Musk better understood the space market, he saw that there was a massive opportunity to disrupt the launch vehicle market, writes Cantrell.
Instead of buying Russian rockets, he decided to spend his time and money "solving the launch problem" and building his own reusable rockets, according to Cantrell.
The company wasn't successful right away even though they had all of the necessary ingredients for success.
"Clearly Elon and the team he recruited were passionate about building a low cost launcher," writes Cantrell. "Clearly we were good at it. And clearly we there was a market."
But they had doubters and most of the world was betting against Musk's success, according to Cantrell. The entrepreneur admits that he internalized this doubt and eventually saw Musk's passion for colonizing Mars as a "fool's errand" that wouldn't happen in their lifetime.
However, he writes, "Elon did succeed in the end and it was because he never counted himself out."
Even with all the naysayers, Musk refused to give up and he kept trudging forward. Cantrell writes, "He knew that he had the three ingredients and he kept upping the ante every time that he faced an obstacle or failure."
This, says Cantrell, is the most crucial trait to achieve personal success: "It's simply a determination to never give up."
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