Billionaire Chris Sacca absolutely shredded the pitch of an entrepreneur duo on "Shark Tank" Friday.
The founders withheld critical information about their business until the very end of the pitch, and the Silicon Valley investor was having none of it.
Savannah Cowley and Samuel Agboola went on the reality television show seeking $375,000, in exchange for a 5 percent investment in their photo printing service, Flag.
The entrepreneurs presented Flag as "the world's first truly free photo printing app." Customers would be able to order up to 20 free prints per month with no shipping charge and no subscription fee. A customer would not need to enter credit card information to receive free prints with the app, they said.
To pay for the service, Flag charges advertisers to put their message on the back of the photos sent to customers.
In the three months prior to pitching on the show, Flag had made $150,000 in revenue from selling advertising to companies, including credit card giant Visa.
Investor Kevin O'Leary expressed concern early on in the pitch. "There's nothing proprietary about this," he said. Competitors could replicate the Flag offering pretty easily.
Cowley and Agboola continued on. They eventually reveal they have already raised $1.6 million and that they are currently seeking a total raise of $3 million. The $375,000 they were looking for from the sharks was only a small portion of the total raise they were in the midst of.
At that point, billionaire tech investor Mark Cuban expressed his frustration at not being told right at the start of the pitch the total funding round the team was seeking. "Oh! You didn't think you should tell us that?" he asked.
O'Leary piled on, frustrated that Flag didn't have enough data yet to show that the advertisers would come back to the table. "I feel like I have to come over and spank you with a ruler because you are on the cusp of the darkness, the abyss, the evil of going to freaking zero with a bullet," he added.
Almost all the sharks had declined to invest when Agboola revealed that the business model isn't entirely dependent on advertising.
"I want to make sure that one thing is clear. This is a freemium model," Agboola said, referring to a pricing structure where only one tier is free, but users pay a premium to get more functionality or access to different features. "We don't anticipate that all of our revenue is going to come from advertising," he added.
It's at that point that Silicon Valley investor Sacca lost his patience and really laid into the Flag team.
"Wait. You guys, we are in the eleventh hour and you are just now going to pivot and tell us you are freemium," Sacca says.
Agboola tries, fruitlessly, to explain.
"Somebody call a doctor because this pitch needs CPR right now," Sacca says. "I mean, you have got to be kidding me. You are bringing that up now. ... Come on."
The billionaire added: "When you guys walked in I thought I smelled a little bit of smoke in the air and then I realized it's from the bonfire of cash you guys are burning back at your headquarters," Sacca said.
"I don't usually invest in businesses that are doing old school ads with a really weak business model in crowded markets with a five-alarm cash burn … And this time is no different. I am out."
Ultimately, the Flag team did not get an investment from either of the sharks on the show. While they didn't walk away with a deal, Sacca's frustration illustrated a key point when pitching investors: Don't keep any surprises from your potential investors.
Be fully transparent as soon as you start interacting with an investor about how your business will make money, what money you have already raised, and what expenses are involved.
Investors put their money on the line, and expect to know exactly what risk they are taking on.
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Disclaimer: CNBC owns the exclusive off-network cable rights to "Shark Tank."
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