"Not everyone leaves happy": Janine Allis on the explosive new season of Shark Tank.

Get your pitches ready.

The next season of Shark Tank is about to hit our TV screens and Shark Janine Allis says we can expect some big surprises this season.

Namely, some very unhappy contestants.

“Not everyone leaves happy. Some people can’t take the truth and some people feel very intimidated by some of the feedback,” Allis told Mamamia.

“Business is about rejection, business is about things going wrong, it’s about dusting yourself off and getting back up. You know, that’s what business is. And if you can’t take a bit of constructive criticism you should not be in business.”

Some of the unmissable moments in the upcoming season include a 17-year-old with a half-a-million dollar doughnut business, someone claiming their business will turn over one billion dollars, and Shark Steve Baxter storming out mid-pitch.

The 53-year-old entrepreneur also hinted that some of the weirdest inventions this season will end up being the most successful.

“It’s probably happened about four or five times,” she explained.

“I walked in and there was one product and I just thought ‘Oh god, shoot me now’ and then I tried to bid on it and I ended up getting it.”

Allis says we might see the Sharks reacting to a strange product on a promo, but then it'll end up being a surprisingly good business idea.

"Often we'll have a reaction to the product as we walk in, and we'll have a little jibe as we sit down, and then it's a very different reaction by the time we actually understand the business.

"I think that will be interesting to see the perception versus the reality."

Allis, who is the founder of Boost Juice and part-owner of Retail Zoo, believes the show is so popular because everyone has at least one good idea.

"Everyone has an idea, but some people don't have the courage or the means or the support to bring it to fruition," she explained.

"It's a show of dreams, a show of how can I live my life differently? How do I get myself out of what I'm doing and do something that I love? How can I not have to answer to anyone else?

"Shark Tank is a show that gives you hope, or gives you the confidence to maybe do something you never thought you could do."

You can watch the first episode of Shark Tank season four on Tuesday, 15 May, at 7.30pm on TEN.