Entrepreneur  Mark Cuban isn't known for his humility. He did, after all, claim he would "crush" both Hilary Clinton and Donald Trump in a U.S. presidential election. 

But Miles Penn, a contestant on last week's  Shark Tank, may have a bravado that rivals even Cuban's. Cuban told Penn, who came into the tank seeking $2.5 million for 10 percent of his company: "You may be even more arrogant than I was, if that's possible."

The sharks liked the concept behind MTailor, Penn's high-tech custom dress-shirt company. MTailor uses your smartphone camera to measure your body type, replacing the role of a tailor. By cutting out the middleman, MTailor is able to sell men's dress shirts for $69 each--$55 less than the usual cost, according to Penn, the company's CEO and co-founder.

But Penn, a 2012 Stanford graduate, started off his presentation with a shot at shark Daymond John's clothing company, saying that "unlike FUBU," MTailor gives customers the ability to specify if they plan to wear their shirts tucked or untucked.

"That's not a good way to start a pitch," John replied. 

Then came this surprise: Penn valued MTailor at a whopping $25 million. This, while he expected to miss his 2015 revenue goal of $2 million by about $900,000 due to issues with Chinese factories. 

"You're a company that misses its numbers by 50 percent," said Kevin O'Leary.

"I can't pay a perfect price for a company that isn't perfect," added guest shark and billionaire angel investor Chris Sacca. "Are your existing investors willing to invest in the same $25 million price, or are you trying to take advantage of the sharks here?"

Penn countered that MTailor was already valued at $10 million and that "if we went out and raised a Series A, that would be a very fair value." The two-year-old San Francisco-based company had raised $2 million from venture-capital firm Khosla Ventures and was a member of YCombinator's summer 2014 class. In 2014, MTailor generated $150,000 in revenue per month, according to Penn.

Barbara Corcoran, seeing Penn as too nonchalant about missing revenue goals, told Penn that she was out.

Penn's response: "Well, you can't please everyone." 

Still, John and O'Leary were impressed enough with the company's technology to offer Penn money. John offered Penn $2.5 million for 17.5 percent on the condition that he could help license the technology. O'Leary offered to loan Penn the $2.5 million at 7 percent interest over 36 months. Penn turned down both deals, after he couldn't persuade John to let go of the licensing condition and Mr. Wonderful declined to turn his loan into equity.

The sharks decided that they had had enough. John told Penn to "just go away."

Penn, for his part, said on the show that he "bent as much as I thought was reasonable for our business." MTailor did not respond to Inc.'s request for comment.