In the startup realm, there is only one constant: change. 

I recall with one startup many years ago, we took advantage of radio ads which, at the time, were very common. Yet our ads didn't yield the results I was expecting. We found soon after that the audience we were trying to reach was not exactly consuming that kind of media on a regular basis and so the return on investment didn't pan out with that advertising strategy. Every year, every five years, every decade, there are changes to so many aspects of how a startup is built and run, including marketing and advertising. 

Marketing has changed radically in the last few years. In some categories, like autos, the traditional purchase funnel doesn't seem to apply anymore. Advertising on TV is no longer the sure thing it once was and in digital, fraud, waste and ad blockers conspire to make that medium less effective.

With so many touchpoints and channels, choosing the right marketing strategy can be overwhelming--I've been there. One increasingly attractive option is to just buy Facebook ads.

While you might think of Facebook as a place to catch up on baby pics and news about your distant friends and relatives, it has emerged as a potent tool for SMBs as well.

Here are some reasons why:

1. Facebook is the new TV. 

Years ago, people used to tune in to TV to watch their favorite programs. Along the way, they'd see ads for new products that, with the proper saturation, often became successful because of such exposure.

But now TV is as wildly fragmented as the Internet. By the end of 2017, some 22.2 million  adults will have cut the cord on their cable or satellite TV subscription, according to eMarketer. That figure keeps rising each year.

Meanwhile, Facebook now commands 50 minutes a day, on average, of consumers' time. This is the new prime time TV.

2. "Lookalike Audiences" is effective for growth. 

"Lookalike Audiences," a Facebook ad product, looks at your existing customers and trolls through the social network's 2 billion members to find consumers who have the same attributes as your existing audience. You only need 1,000 customers (or 1,000 of your best customers preferably) to find a Lookalike Audience.

One entrepreneur, Steph Korey, a founder of luggage company Away, told The New York Times that she got $5 back for every $1 she spent on Lookalike audience ads. That's a solid ROI on advertising spend.

3. Facebook's AI algorithm helps you pick the best ad. 

If you are a startup or small business advertiser and don't work with an ad agency, then it can be hard to figure out which ads will work the best -- after all, advertising isn't your primary business.

Facebook addresses that void by using artificial intelligence software that tests each ad's effectiveness. Instead of focusing on meaningless metrics like engagement, Facebook also looks at lift, which tests an ad's effect via randomized control trials. Such RCTs compare the desired actions (like purchasing) of a group that was exposed to an ad to a control group that hasn't been exposed to the ad.

4. You can market-test new ideas. 

Why go to the trouble and expense of following through on a product launch when you can test it in real-world conditions for a few hundred dollars? 

Facebook's Lead Ads let you run an ad even if you don't have a website. If consumers are interested, they click on the ad and submit their email addresses from Facebook. That's a great way to assess demand without spending a lot of money. (Caveat: If you are collecting an interest list, be very transparent with consumers that your product or service is not offered yet or you can get into hot water for violating false advertising laws, FTC regulations and similar laws designed to protect consumers from fraudulent or misleading inducements online.)

Facebook ads work best if you're targeting consumers. If your product is more B2B-focused, then LinkedIn might be a better venue. If you're adept at creating video, then YouTube rivals Facebook's reach and may make more sense for you.

For most small businesses though, Facebook provides a level of targeting and sophistication that was unavailable a few years ago. It's no wonder then why many startups are building their companies around Facebook-based marketing campaigns. Such entrepreneurs realize that Facebook is no longer about baby photos and wedding announcements, it's about using the data of 2 billion people to supercharge your marketing.