In early May of 2021, ABC extended 'Shark Tank' for yet another season, the 13th believe it or not. In total, the show has released a near 300 episodes. Despite its longevity, it continues to be a monster hit.

A big part of the reason, the sharks attached to the show, which includes Kevin O'Leary, Mark Cuban, Lori Grenier, Robert Herjavec, Daymond John, Barbara Corcoran, and so many others.

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The show inspired international versions as well, including Australia, Mexico, Columbia, India, and a handful of others.

As it turns out, according to a cast interview alongside 'Vulture', the show's success was never a guarantee and in fact, the idea was one previously used in Japan on a show called 'Dragon's Den'.

Early season ratings weren't soaring either and the casting process was a little more complex than most would think. In fact, one of the more beloved sharks on the show was initially told no by ABC. Thanks to the producers, he eventually got on but it wasn't without a struggle.

Let's take a look at the tough casting process along with which shark was told no by ABC at the start. We can all agree, including him in the following season changed everything for the show.

Casting & Early Struggles

Clay Newbill and Yun Linger would admit that the show's concept was not a new one, though they wanted to put their own spin on it.

"The show is a format that has been around for quite a while, based out of Japan. It’s called Dragon’s Den. By the time we got it in the U.S., it was in 30 territories, but we had a bunch of ideas for what we could do for the American version and the hosts."

The show had its struggles early on, along with ratings, the set was extremely outdated, "The first set was horrific, we couldn’t look at it much longer! There was a little bit of fine-tuning, but as far as the structure of the show, we stayed the same."

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Getting to appear on the show as a panelist wasn't exactly easy either. Barbara Corcoran admits that the process was an intense one, and she had to go as far as to show her financial statements.

"I had a very intense interview that I want to share. They asked me to send them my financial statement. I did, and they said, “You’re in.”

As for Kevin, the process of getting him on the show was a little easier, given he was already on 'Dragon's Den' over in Canada.

"Yeah, I had done the format with Robert in Canada. I got a call from Mark Burnett and he said, “Come to ABC, I’m working on a new idea called Shark Tank. It is very similar to Dragon’s Den and we need an asshole.” I said, “I’m your man.”

The process was a little different for a certain star on the show. In truth, who knows if the show would've survived had they kept him off. Once he entered the tank, everything changed, especially the ratings.

Mark Cuban Was Told No

It is hard to imagine, but Mark Cuban admitted alongside Vulture that he was told no by ABC at the start. Though luckily, he constantly had the backing of the producers and creators of the show.

"It wasn’t Mark and Clay. It was ABC," Cuban stated.

Robert was swiftly brought in to replace Cuban, though ultimately, Mark landed on the show.

Believe it or not, Cuban credits the HBO show 'Entourage' for getting him a spot on the show. It showed a little more of his personality, as he revealed with 'Page Six'.

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"Yes, 100% it helped. “I get there thinking I’m going to do my little spiel, typical cameo, and I all of a sudden Doug’s like, ‘We’ve got this storyline …'”

He thrived on the show and the same would take place in 'Shark Tank', as he boosted the ratings and became a must-have shark for those on the show.

Ultimately, Cuban wants the lasting impression of the show to be one that motivates others, "Our legacy is going to be, when you watch enough Shark Tank, you’ll know what to do. That’s the message we want to leave."

"With an idea, with effort, with a little bit of chutzpah, anything is possible no matter who you are, what you look like, or where you’re from. If that’s our legacy, I’d be very, very happy."

ABC is definitely happy they reconsidered...

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Sources: Vulture, YouTube & Page Six