Part of what makes Shark Tank great is the unscripted, real-life quality that no longer exists in most reality television. As a result, most fans know by now that none of the entrepreneurs who pitch their businesses are actors, that Mark Cuban and the other sharks really do invest their own money, and many other facts about the show. Still, there are many aspects of the hit business-themed series--and what it's like to be a shark--that end up on the cutting-room floor. Here are 10 things that may surprise you. 

1. Shark Tank got its start in Japan.

The first precursor to Shark Tank was a reality show that debuted in Japan in 2001 called Money Tigers. In 2005, a production company in the United Kingdom licensed the concept to create a British version called Dragon's Den. That show spawned a Canadian spin-off that both Robert Herjavec and Kevin O'Leary took part in before they became "sharks" in the U.S. series, which reality-show producer Mark Burnett developed in 2009. Other countries with their own versions of the show include the Czech Republic, Finland, Poland, Spain, and Ukraine.

2. Shark Tank is harder to get into than Harvard. 

Of the 45,000 people who applied to be on the show in 2014, less than 1 percent got the opportunity to pitch their businesses to the sharks. Out of that group, many entrepreneurs never saw themselves on TV, as only the pitches that make for good reality TV see the light of day.  

3. Shark Tank was not a popular show at first.

The first season of Shark Tank didn't even break the top 100 primetime shows in terms of average viewership. It was only after Mark Cuban joined in season 2 that the series began to grow its audience. Season 5 attracted an average of more than 8 million weekly viewers, up from 4.8 million during the first season.

4. ?The vast majority of what happens in the tank never actually makes it on TV. 

Most pitches take about an hour before a deal is made or all the sharks opt out of investing, but each segment is edited down to just 10 minutes. Some of the worst pitches get dismissed in as little as 20 minutes. The longest pitch in the show's history, according to Cuban, was Michael Tseng's microwave-safe food cover PlateTopper. The pitch lasted two and a half hours before Lori Greiner invested $90,000 for 8 percent of the company. 

5. The sharks love talking trash--even when they're not in the tank.

All the sharks have friendly relationships, but that doesn't mean they pass up opportunities to throw each other under the bus. "Kevin [O'Leary] is a jerk on camera and he's a bigger jerk off camera," Mark Cuban joked at Inc. magazine's 2014 GrowCo conference. "I'm sure they say the same things about me. Robert [Herjavec] is a great guy, but he's so syrupy. And he's so naive too."  

6. The simplest ideas often make the most money. 

While many entrepreneurs come to the tank with a mobile app or other tech product, some entrepreneurs have scored big in the marketplace with remarkably simple consumer goods. Screen door repair product ScreenMend, for example, went from $4,000 in sales to more than $1 million in a single year. All-purpose cleaning tool ScrubDaddy has done $50 million in sales, according to Greiner, making it the most successful product in Shark Tank history. "If you have one genius product and good entrepreneurs, you can turn that one product into a huge success," she says.

7. The sharks back out of a lot of deals. 

The agreements made on the show between sharks and entrepreneurs are non-binding handshake deals, and many of them never close. Why not? Entrepreneurs have been known to fudge some of their company's financial figures, or make false claims like they have a patent on a product. When the sharks look under the hood of the companies they've agreed to invest in, they frequently don't like what they see and back out. 

8. Shark Tank entrepreneurs also back out of deals.

The percentage of entrepreneurs who experience seller's remorse after making a deal on the show has grown during the past few seasons, according to Robert Herjavec. "A lot of people come on and change their mind," he says. "I would say 90 percent of the time it's the entrepreneur [who backs out]." During the most recent season, for example, entrepreneurs Ellie Brown and Becca Nelson agreed to sell 100 percent of their wearable fabric sticker company evREwares to Mark Cuban for $200,000 before changing their minds and deciding not to sell.

9. Shark Tank provides a major boost even for the companies that don't make a deal. 

Entrepreneurs can expect to see a spike in sales after their episode airs, even if they leave the tank empty-handed. This has attracted what are known as "Shark Tank gold diggers": entrepreneurs who have no intention of selling a piece of their company, but come on the show just for the publicity. "We're getting better at spotting the people who are obvious about it," Herjavec says.

10. Being a shark can be grueling. 

If the sharks always appear hungry when an entrepreneur offers them food, it's because they usually are. Show tapings last all day, and sessions typically go for 10 days straight. In that time, the sharks will hear roughly a hundred pitches. "We're there 12 hours a day," says Herjavec. "We're hungry and we're miserable."