Passion will only get you so far with these investors.
Self-made millionaires Michael "Rooster" McConaughey and Wayne "Butch" Gilliam, veterans of the oil-and-gas pipeline industry, aren't too keen about an emotional entrepreneur.
For Gilliam, being overly passionate is the worst thing you can do in business.
"When these entrepreneurs come in here with these ideas, there are so many times that they are so passionate about it that they are not able to look at it in a black and white format," he said.
"They are trying to present it to us in an inflated, hopeful, dreamlike presentation and I just wish that they would come to us with the reality of the deal."
McConaughey noted that entrepreneurs who are too emotionally connected to their products can actually complicate a business deal.
"Make it elementary," he said. "The deal should stand on its own."
Watch "West Texas Investors Club" on CNBC Tuesday at 10 p.m. ET.