YouTube CEO Susan Wojcicki arrives for the annual Allen and Co. media conference Sun Valley, Idaho, July 7, 2015. REUTERS/Mike Blake

A funny thing happened at New York City’s Javits Center on Thursday night. YouTube CEO Susan Wojcicki took the stage in front of a massive crowd at the YouTube “NewFront” presentation to advertisers and opened verbal fire on the TV industry.

“Today, I’m happy to announce that on mobile alone YouTube now reaches more 18-to-49-year-olds than any network — broadcast or cable,” Wojcicki said. “In fact, we reach more 18-to-49-year-olds during prime time than the top 10 TV shows combined.”

The statement immediately made its way around the internet. After asking YouTube for its methodology, International Business Times can confirm while it’s technically an accurate statement, it’s still, well, a weird comparison to make.

Youtube Inc. | FindTheCompany

YouTube arrived at its claim by asking media research giant Nielsen to look at the number of people 18-49 who watched at least one YouTube video on their smartphones during prime-time hours in the month of December, and compare that to the number of people 18-49 who watched at least one TV network during prime-time hours in December. These numbers came, respectively, from two of Nielsen’s sample groups: its mobile panel, and its TV panel.

What this comparison leaves out is length of tune-in, which might seem unimportant, but does truly matter, and not just to advertisers. Think about it this way: These figures give the same weight to a person who watched a single 30-second video of a cat in a cardboard box as to a person who watched an entire episode of Fox's “Empire.”

Where people watch things matters as well. Two-thirds of YouTube viewing is now done on a mobile device. However, while mobile video viewing is skyrocketing, and more people are watching their shows on mobile devices or devices connected to their TVs, the Nielsen study counted only those who watched TV in the traditional way.

Think about how many YouTube videos you come across in your daily life just by scrolling through Twitter on your phone, or that you receive in a texting app or by email. Compare the ease of watching any of these videos with the act of getting to and sitting in front of a TV. In fact, you can even watch YouTube videos on your phone while watching TV.

There’s the matter of when these people were doing this watching, as well. YouTube had Nielsen look at data from December, a month when prime-time airing schedules are erratic and many shows are on hiatus. December also has lower numbers of people watching TV in general — peak TV months are October, November and January through April.

So of course YouTube “reaches” more 18-to-49-year-old viewers “just on mobile.” That’s likely been true for a while.

Wojcicki’s point, ostensibly, was that advertisers should be looking beyond TV for young eyeballs, and YouTube has plenty of them to offer. But what’s fascinating about this claim is that YouTube doesn’t need to make it.

Everyone knows YouTube has a mind-bogglingly large, young audience. That’s one of the reasons Magna Global, the massive ad-buying arm of Interpublic Group of Companies, is taking $250 million from its clients’ TV budgets for October 2016 through December 2017 and dumping it into YouTube.

(For context, Magna typically handles $5 billion to $8 billion per year on TV ad spending, domestically.)

Even using “18-49” as the basis is odd. TV advertisers themselves have long chafed against the tyranny of “the demo” (as it’s referred to in the industry). Many deals are still made using guarantees of the 18-49 demographic, but most companies are looking for more specific marketing targets, and TV networks have gotten more sophisticated with their sales pitches in response.

NBCUniversal, in fact, says this year it’s going to start making ratings guarantees that aren’t based on the traditional Nielsen demos. Agencies themselves, internally, conduct their own research into creating media plans that deliver the highest number of target audiences that generally don’t conform to simple age and gender demos.

So yes, YouTube might be reaching more of the demo than TV, by its definition of reach. But as any marketer will tell you, reach is just the beginning. YouTube knows this as well, which is why it has introduced the concept of “Google Preferred” ad inventory, which offers up slots in premium videos to advertisers at premium prices — no cat-video compilations here; instead, advertisers get slickly produced content guaranteed to get millions of views. Sounds a little familiar to us.