If you think money and intelligence are all you need to be successful, think again.
According to entrepreneur Jim Cantrell, who worked with Elon Musk as part of SpaceX's founding team, these two factors comprise a small part of what it takes to achieve tremendous success.
"Intelligence is more of a tool that enables you to be successful rather than an ingredient itself," Cantrell writes in a Quora post that offers guidance on becoming successful, which was first published in Forbes.
As the head of SpaceX, one of Musk's most recent achievements came earlier this year when the aerospace company launched a rocket carrying a Tesla Roadster to space, making it the most powerful commercial rocket in the world.
Separately, SpaceX booked its first private passenger to fly around the moon aboard its BFR aircraft. The identity of the traveler was revealed at the company's California headquarters during an event Monday evening.
The Apollo mission in 1972 was the last manned voyage, one that only 24 other humans have ever made.
Though Cantrell is no longer employed at SpaceX, his years of experience advising billionaires and tech companies coupled with his extensive work under Musk, have presumably taught him what true success takes.
Success, he writes, relies on a "single simple formula" that's based on three things, which Bill Gates, Mark Cuban and Jeff Bezos seem to agree on as well:
Do what you're most passionate about in life. "Without passion, your work is not your love and you can never be your best or be better than others who are running with their passion," Cantrell writes.
Other highly successful people have said the same. In a Q&A with ABC.net, Microsoft co-founder Bill Gates says: "If you're lucky when you're very young, you find something you're passionate about. I did when I was 13 years old. I found computers and software."
"Do something that you are inherently good at or talented at," writes Cantrell. Pursuing work that's difficult, and in which you lack skill, puts you at a disadvantage to more talented people within the same field, he explains.
Billionaire entrepreneur Mark Cuban echoes this sentiment, noting that aptitude and effort are often what lead to passion. He uses himself as an example.
One of the billionaire's first post-college jobs was to sell software at a store, which required that he learn how to use a PC system. Although Cuban had barely taken any tech-related courses while an undergrad, the entrepreneur taught himself how to use the software and in doing so, fell in love with computer technology, he wrote in a 2012 blog post.
"I could go seven hours, eight hours without taking a break thinking," writes the "Shark Tank" star. "That's when I realized that I can be really, really good at technology,"
Years later, Cuban launched computer consulting service, MicroSolutions, which he sold to CompuServe in 1990 for $6 million.
"When you are good at something, passionate and work even harder to excel and be the best at it, good things happen," notes Cuban, who now has a net worth of $3.9 billion.
You can have the best idea in the world and the most enthusiasm about it, but if nobody wants it, then it's a dud, says Cantrell.
"Do something that creates value and can be sold into a market present or future," advises the entrepreneur. While creating a product or service can be "self satisfying," he writes, the business won't "make you your fortune nor lead you to personal or professional success" without consumer demand.
Amazon founder, and now the richest person in the world, Jeff Bezos prescribes to this theory. The retail giant was able to expand so quickly because Bezos offered a service that customers found valuable: a wide array of products on a convenient online platform.
When Amazon was first launched, the company only sold books. Shortly after, Amazon added music and videos. Looking to expand its producer offering even further, Bezos reached out to customers in order to gauge what they wanted to buy.
"The list came back incredibly long," Bezos told Charlie Rose in a 2016 interview. Yet he listened to consumers, giving them what they valued and were willing to pay for. This customer-obsession is now at the heart of the company's culture.
"We are always focused on the customer, working backwards from the customer's needs, developing new skills internally so that we can satisfy what we perceive to be future customer needs," Bezos told Rose.
In the list above, Cantrell again emphasizes that money and intelligence are not key factors. "If you combine these three elements into your pursuits in life," he writes, "you will be very successful and the money will come on its own."
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This is an updated version of a previously published article.