With hard work, perseverance and luck, four men who worked as janitors early in their careers became self-made millionaires.
While the job was a choice for some, it was a necessity for others, but being janitors taught them the keys to success and gaining wealth through smart investing, creating opportunities and making each day count. Here are their inspiring stories.
At the Iconic Tour in Los Angeles, Tony Robbins discussed how he had no trouble cleaning floors and putting in a little extra elbow grease into his work while young, especially if it meant one thing: freedom.
"I used to work as a janitor and I picked that job not because I like janitoring but because I could do it literally from 10 to 2 in the morning," Robbins says.
Being a janitor allowed him to not only work more, but also faster and better. "I also had the free time to think and feed my mind," he says.
By working the part-time janitor job making $40 a week, Robbins was eventually able to invest in himself and form a billion-dollar empire through being a founder or partner at over a dozen different companies.
"I think if you can find a place where you can do something that gives you freedom and gives you a chance to really take control of your own time, it leads toward the idea of maybe owning your own business," Robbins says.
An immigrant from Ireland, Sean Conlon arrived in Chicago with $500 and started out as an assistant janitor.
Back home, his family hadn't had much. Once, a bank had even tried to repossess his family house, which may have inspired Conlon to become a real estate mogul (and the star of CNBC's "The Deed: Chicago").
Conlon worked hard to save money, which he eventually used to buy his first apartment. He began selling real estate at night, and ultimately became one of the top real estate brokers in the country.
And he credits much of his success to the possibilities in the United States. "I understood fairly quickly that real estate is a tangible path to wealth," says Conlon. "I was an ordinary person who did some fairly extraordinary things. It's America. You can still do those things."
Once a janitor and gas station attendant, Vermont's Ronald Read quietly became a self-made millionaire without a hefty annual salary.
Read, who passed away at age 92 in June 2014, put together an $8 million portfolio, one even his family didn't know about until his death.
He reportedly had at least 95 stocks when he passed away and was said to live a frugal lifestyle. Read gave most of his wealth to the hospital and library in Brattleboro, Vermont, where he lived his entire life.
Originally from Ohio, Hightower worked nights and weekends for his family's cleaning business. He continued working as a custodian in college as well.
Now Hightower has his own oil and transport business, which he started in 1981. In 2017, the company aims to make $500 million.
"I started as a janitor. I started cleaning floors and toilets and doing those things that most people would never even dream of doing," says Hightower. However, he adds, "I wanted more."
"When people ask me would I ever have imagined I would be where I am today? Absolutely," Hightower tells CNBC. "Because if you don't think that you can be great, you'll never be great. And I knew that I was gonna be great a long, long time ago."
The oil tycoon explains that his experience starting from humble beginnings has had a huge impact on his life today. "I still haven't made it. I'm still a very humble individual who's trying to do the best that they can and one day actually make it," says Hightower. "Because I understand what real money is."
Like this story? Like CNBC Make It on Facebook.
This is an updated version of a story that appeared previously.