The following post was originally published in WorkIt Richmond, a small business news and resource publication.

I was recently having dinner with my girlfriend and her younger cousin, who recently graduated high school and is preparing for the big move to college. Our conversation consisted of the usual: what are you going to study? Why did you pick your school? What are you most excited about? My girlfriend and I then began to reflect on our years at school, offering our own infinite wisdom and advice.

I recalled one particular sociology class in my sophomore year. The professor brought up Facebook.

"Show of hands," she said. "How many of you are on The Facebook?" Only a few in a lecture hall of over 300 raised their hand, and you can bet, the number of people who had HEARD of Facebook wasn't much more.

This was 2005. Facebook had just turned one. By the spring of 2005, the social network was still limited to university students and the University of Delaware (my alma mater) had just been put on the whitelist. After seeing the ratio of girls in my class that were on Facebook, I made a strategic decision to join Facebook.

That was eight years ago. Since that time, Facebook has grown into one of the most recognizable brands in the world with a reported 1.15 billion users as of June 2013. With 2.5 billion internet users in the entire world, that's pretty significant market penetration.

Needless to say, Facebook is king. If you are to invest your time on any social network, it has to be Facebook, right?

Right??

Let's jump back to the conversation with my college-bound friend. As a marketer, I can't pass by an opportunity to see how this up-and-coming generation uses the Internet, so I ask her what social networks she and her friends use.

"Not Facebook."

Wait, what? NOT Facebook?

"I have a Facebook, but I never go on it. Same for my friends. We use things like Twitter or Snapchat or Instagram or Pinterest instead."

This story isn't unique. A recent piece written by a 13-year old and published on Mashable explained why Facebook wasn't the "cool" network, and why the author’s friends choose to spend their online time on networks like Instagram, Vine, and Snapchat. The author’s points aligned with what my girlfriend’s young cousin told me: teenagers want their own social spaces away from parents and relatives.

Ok, a couple personal stories are nice. But what does the data say on the topic?

A survey done mid-2012 by the Pew Research Center showed 94% of teens have a Facebook profile. Only 26% of teenagers surveyed had a Twitter profile, followed by Instagram at 11%, MySpace and YouTube at 7%, and Tumblr at 5%.

So another check mark for Facebook. Not only is it one of the largest networks, it seems to dominate the teenage demographic as well. Furthermore, Facebook CEO Mark Zuckerberg, citing internal Facebook data, that the number of teens on Facebook has held steady over the last year and half. On the surface, there doesn’t appear to be a mass exodus going on.

But we’re after something slightly different. We want to know what platforms teenagers actually use on a regular basis. Not the platforms they simply have a profile on.

Big difference.

Do you have an unused Twitter, Instagram, Pinterest, or Google+? You’re not alone. But every time these networks boast the number of users, you’re included in that tally. Misleading, isn’t it? And while Pew and Zuckerberg report encouraging numbers, they could be grossly inflated by teenagers who have rarely-used Facebook profiles.

As marketers, the only reason we care about this information is because we need to know where the eyeballs are and where they’re going. A Facebook profile that’s active but rarely used does not get eyeballs and is not worth our marketing time and money.

The challenge becomes how to interpret all this information so we can make the best strategic decisions.

No social network is invincible to changes in consumer preference. Facebook is more than capable of becoming the next MySpace. Facebook's sheer size, while one of its greatest assets, can also be a detractor for younger generations looking to have something of their own. The same way previous generations rebelled against the social norm through music, today’s teenagers could be rebelling via their social network preference.

For decades, youth have used music as their way to identify themselves and separate themselves from their elders. As others followed in their path, the listeners became more abundant, the space became crowded, and the early adopters eventually left in search of the next new thing.

Is using Twitter abandoning Buddy Holly for The Beatles? Is instagraming swapping The Beach Boys for Black Sabbath? Is snapchatting dropping Guns ‘n Roses for Nirvana?

Market research can’t always predict these sways in consumer preference, especially when they happen so quickly. In a lightening-speed digital world, we can’t always afford to wait for surveys to be gathered and for data to be analyzed. It’s a delicate balance between staying on the leading edge without ignoring the here and now.

At the very least, marketers need to know that Facebook is not the only viable channel for reaching younger demographics. While the data can serve as a good starting point, it must be viewed with a critical eye. History has shown repeatedly how quickly a king can fall. Our job is to be ready for when it does.

As chief marketing officer of WebStrategies, Inc., Chris helps small businesses reach and connect with more customers online. He is the chief strategist for inbound marketing campaigns and the lead analyst for web analytics and website usability testing. Find Chris on Google+, LinkedIn, and Twitter.