I recently witnessed a pitch by the representative of a Central Canadian biotech company that had a product that sounded spiffy, but damned if I could figure out what the guy was saying. The pitch involved a string of medical jargon—and while I did understand that the founder and his team were developing a revolutionary drug, I only gained a vague sense of what the company, for which he as trying to raise $2 million, was doing.

When I was in a group session with the fellow later that morning, I wanted to discuss the wording of his pitch, but someone asked him first about his fundraising. He explained that he was focused entirely on American venture capital funds. He had tried pitching to angels but learned that angels don’t back drug-discovery companies.

It was the clearest example I had seen of a start-up founder jeopardizing his company because of his inability to communicate in clear English. But he’s by no means alone. The sad fact is that too many founders place their companies in danger because of their use of jargon.

Do you think I’m exaggerating? I’m not, because cash is the lifeblood of a start-up. Companies without money die. Yes, you can get cash from government programs, but many of them will only match funds in the company’s bank account, which means outside investment is essential. Funding, especially seed funding, happens when you find a handful of investors who see a profound opportunity—and you’ll poison the pool if you’re unable explain the opportunity to them.

I believe the biotech founder I described above alienated angel investors because they couldn’t understand what he was doing. His company sounded intriguing, and his technology could be something explosive.

By most estimates, angels invest about $3 billion a year in Canada. Yet VC funds in 2012 invested only on $368 million in life sciences companies, according to Thomson Reuters. So the aforementioned exec shrank his market for capital dramatically by ignoring angels, who will back drug-discovery companies if they’re convinced there’s a big opportunity.

Even VC fund managers complain about founders who can’t explain what their companies do in terms everyone can comprehend. The more I learn about start-up communities, the more I believe that jargon is cancerous to young companies.

We all use jargon to some extent because it binds us to those who also use it and we think it makes us sound intelligent. But brilliant people often inflict needless damage on their companies because their spoken and written communications are hindered by jargon.

What’s more, people who spout technical terms can be intimidating—so much so that most of us won’t admit that we don’t understand what they’re saying. It’s easier to smile, nod, and move on to the next pitcher.

Most people learn to communicate about technology in university. Sadly, too many academics—in the humanities, as well as the sciences and business—consider it a badge of honour to use jargon. They get away with it because they’re judged exclusively by other academics. Academia might sound different if professors’ livelihoods depended on pitching for money.

Start-up founders can’t afford such a luxury. The pitchers at the recent Atlantic Venture Forum were speaking to panels of professional investors, and you could see the targets’ eyes glaze over when the presentations got too technical. In my next column, I’ll suggest some tips on how to improve your communications.