A Warby Parker pamphlet arrives in the mail. A Glossier billboard hovers above Houston Street. Clones of an Away wheatpaste coat a construction barrier. A Stitch Fix TV ad blares from the television.

This marketing shift toward brand advertising is an interesting turn of events for the generation of digitally-native brands that were born on the backs of Facebook and Instagram advertising. Why would you pay for a billboard when you could buy a Facebook ad, or mail a catalog when you could send an email? As the de facto growth tool for the digitally-native playbook, surely these digital advertising methods are more effective than the analog ones.

Yet paradoxically, the shift is driven both by the rising costs of digital advertising channels and the ad products available to companies, which are only marginally improving. Facebook and Instagram ads work on a market-based system. This means that the more competition there is for affluent consumers living in NYC, SF and LA—which, let’s face it, is where most of these brands are building their customer bases—the more prices will rise. From 2011 to 2017, the average price for Facebook ads grew more than 14 times—a staggering price increase with very serious consequences for brands. More brands have flooded the scene since then, and prices are likely still rising, especially as Facebook nears peak ad load.

Facebook ads, and direct-response advertising more broadly, offer two unique benefits: 1) the ability to track the effectiveness of an ad with extreme precision; and 2) the opportunity to significantly increase ad spend in minutes, which drives an immense amount of sales. Basically, if a brand spends a dollar, it knows exactly what it will get in return.

These two features made Facebook advertising the method of choice for digitally-native brands, especially because the site’s metrics were very easy to report to the venture capitalists funding the companies. Customer acquisition cost (CAC) and lifetime value (LTV)—the two most trackable metrics for digital advertising—are like oxygen for many of these brands.

But as digital costs continue to rise, especially as Facebook keeps tweaking its algorithm, brands have been forced to look for different channels—billboards, wheatpastes, direct mail, magazine spreads and other, less-targeted forms of brand advertising. These moves take a page directly out of the traditional brand-building playbook, which opted for bigger, splashier and less ROI-driven campaigns, partially because it was more “fashion” and also because Facebook, Instagram and Google didn’t exist.

While the cost of brand advertising might be lower, there’s less assurance that these ads will lead to sales. Outdoor Voices can put up a billboard in Austin, Texas, its hometown, but it’s much harder and more time-consuming to track its effectiveness. The same could be said for a Stitch Fix TV ad, a channel that the retailer is increasingly tapping into to broaden its customer base—the company increased its advertising spend by 84% in the first quarter of this year, diversifying its acquisition methods to more traditional forms of brand advertising. These old-school methods build “brand affinity” which is important, especially if the goal is to build a long-lasting brand, but the methods are untrackable and it takes more time for them to pay off—if they do at all.

If brands are going to increasingly rely on traditional methods—and doing so seems like a smart short-term and long-term diversification strategy—they will need to recalibrate their own and their investors’ expectations. With non-digital advertising, the brands won’t instantaneously receive metrics that calculate the effectiveness of these channels. That doesn’t mean they won’t work—they definitely can—but making them work requires reforming the digital-only foundation that many of these brands were built on. Just as their sales channels are evolving from purely digital to increasingly retail and wholesale, their marketing spends will do the same. Facebook is not the silver bullet.