Grant Cardone went from broke and in debt at 21 to self-made millionaire by 30.
"Getting rich and becoming a millionaire is a taboo topic," he writes on Entrepreneur. "It shouldn't be taboo and it is possible."
That is, if you think big enough, the entrepreneur and best-selling author emphasizes: "The single biggest financial mistake I've made was not thinking big enough. I encourage you to go for more than a million. There is no shortage of money on this planet, only a shortage of people thinking big enough."
He's not the only self-made millionaire to encourage this level of thinking. After studying a number of wealthy people, self-made millionaire Steve Siebold found that rich people set their expectations high — they aren't afraid to think big.
After all, "no one would ever strike it rich and live their dreams without huge expectations," he writes in "How Rich People Think."
The bottom line: Aim for $10 million, not $1 million, the self-made millionaires encourage.
"To think that you can't get your share is ridiculous when you consider that there is approximately $41 trillion dollars in global circulation," Cardone writes. "There is a greater shortage of people going for 'more money' than there is money. Sounds like a simplification but my entire financial world changed when I realized there was no shortage except for the one in my mind."
CEO Mark Zuckerberg gestures while delivering the keynote address at the Facebook F8 Developer Conference Wednesday, March 25, 2015, in San Francisco. (AP Photo/Eric Risberg)
FILE-In this Thursday April 26, 2012, file photo, Dustin Moskovitz co-founder of the collaborative software company Asana, poses outside of his office in San Francisco. Facebook co-founder Dustin Moskovitz has been selling 150,000 shares of Facebook stock a day out of the hundreds of millions that he owns. So far, he has shed 1.35 million shares for proceeds of $26.2 million, at prices ranging from $18.79 to $20.08. (AP Photo/Eric Risberg)
Billionaire Elizabeth Holmes, founder and chief executive officer of Theranos Inc., speaks to the media as she arrives at a state dinner hosted by U.S. President Barack Obama and U.S. First Lady Michelle Obama in honor of Japan's Prime Minister Shinzo Abe at the White House in Washington, D.C., U.S., on Tuesday, April 28, 2015. Prime Minister Shinzo Abe goes before the U.S. Congress on Wednesday to present Japan as a stalwart ally that's willing to play a bigger military role in Asia, a message likely to be embraced in Washington and greeted with suspicion in Seoul and Beijing. Photographer: Andrew Harrer/Bloomberg via Getty Images
Nathan Blecharczyk, co-founder and chief technology officer of Airbnb Inc., speaks during the 2015 Bloomberg Technology Conference in San Francisco, California, U.S., on Monday, June 15, 2015. The conference gathers global business leaders, tech influencers, top investors and entrepreneurs to shine a spotlight on how coders and coding are transforming business and fueling disruption across all industries. Photographer: David Paul Morris/Bloomberg via Getty Images
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Airbnb online accommodation provider co-founder and Chief Product Officer, Joe Gebbia announces to the media their partnership with the Brazilian Olympic Committee for the Rio 2016 Olympic Games at the headquarters of the Brazilian Olympic Committee in Rio de Janeiro, Brazil, on March 27, 2015. AFP PHOTO / YASUYOSHI CHIBA (Photo credit should read YASUYOSHI CHIBA/AFP/Getty Images)
PARIS, FRANCE - JANUARY 26: Tatiana Casiraghi attends the Christian Dior show as part of Paris Fashion Week Haute Couture Spring/Summer 2015 on January 26, 2015 in Paris, France. (Photo by Pascal Le Segretain/Getty Images)
NEW YORK, NY - APRIL 22: Snapchat co-founder and CEO Evan Spiegel speaks during the iHeartMedia Soundfront at iHeartMedia Headquarters on April 22, 2015 in New York City. (Photo by Michael Loccisano/Getty Images for iHeartMedia)
Bobby Murphy, chief technology officer and co-founder of Snapchat Inc., speaks during a Google Inc. Cloud event in San Francisco, California, U.S., on Thursday, March 25, 2014. Google Inc. cut prices on some Internet-based services for businesses by 30 percent or more, stepping up a challenge to Amazon.com Inc. and Microsoft Corp. in cloud computing. Photographer: David Paul Morris/Bloomberg via Getty Images
Snapchat co-founders Evan Spiegel and Bobby Murphy attends the Time 100 Gala celebrating the Time 100 issue of the Most Influential People In The World at Jazz at Lincoln Center on April 29, 2014 in New York. AFP PHOTO / Timothy A. CLARY (Photo credit should read TIMOTHY A. CLARY/AFP/Getty Images)
Adrian Cheng, executive director of Chow Tai Fook Jewellery Group Ltd., attends the companys annual results news conference in Hong Kong, China, on Tuesday, June 18, 2013. Chow Tai Fook, the worlds largest listed jewelry chain, reported a 13 percent decline in profit on higher costs and weaker consumer spending. Photographer: Jerome Favre/Bloomberg via Getty Images