Last year, Google introduced local search ads and promoted pins to wring a few extra dollars out of Maps. By extra, I mean potentially an additional $1.5 billion in 2017 alone. Maps inherently have local intent; local intent has a high likelihood for conversion. No surprises there.

But ads run counter to a quality user experience.

We as advertisers can perform all the mental gymnastics we want, but the truth is, ads are a nuisance. Especially on maps. When you’re looking for a location, the last thing you want to see is a map resembling a pincushion or a shotgun’s scatter pattern. Striking the right balance between organic and paid listings is critical.

Unfortunately, as the screen size shrinks, the challenge of balancing paid and organic gets magnified on the map. On desktop, there aren’t so many paid ads that you can’t find organic listings. In fact, it’s almost a happy compromise. You get to use Google’s mapping services for free; Google gets to turn a profit. Fair deal.

With mobile devices, populating local searches with ads becomes less user-friendly. Paid ads shove organic listings toward irrelevancy, and small businesses can’t always afford to pay for those critical ad spots. Still, it’s workable.

But voice search is becoming a fundamental aspect of local search. And voice search tends to eliminate the screen entirely. This creates two problems. One, how do Google, Microsoft and Amazon display a map without a screen? And two, how do they make money off the map if you can’t see it?

Problems with visualizing the map

When it comes to general knowledge queries, you can get by without a screen. Ask a search engine what’s the airspeed velocity of an unladen swallow, and it will simply tell you the answer (assuming you’ve specified African or European).

But the visual component of a map is rather critical. Sure, Google will read us directions when we’re driving, and we function (more or less) without looking at the map on our phones. But this is after we’ve made a decision to go somewhere, not before it. When you conduct a voice search for nearby restaurants, it’s difficult to choose a location if there’s nothing visual to look at.

This is the problem with in-home digital assistants like Google Home and Amazon Alexa. Are we just supposed to wait patiently while the digital assistant reads us a laundry list of 10 nearby locations before deciding? Doubt it. Are we simply going to trust the one location the digital assistant serves up? Probably not — even if someday that’s possible.

With Big Data and predictive analysis, search engines will get pretty darn good at serving optimized search results for each user. On the surface, this seems like a great way to winnow down the number of search results.

Only there’s a problem. Google and the others don’t rely on you picking the best answer; they rely on you picking the paid answer. Once you get to a certain point, providing optimized organic results runs counter to the business models of these companies.

So that brings us to the real question: How will Google, Amazon and the others make money from paid voice search?

Problems with paid voice search

The problem with selling ads through voice search, whether they have local intent or not, is that it erodes user trust. If the only answer Amazon Alexa provides is an ad, why would you trust any of its search results?

Granted, no search engine would be foolish enough to go this extreme route. But even if you’re giving only one paid answer to every three organic results, it’s no longer easy to ignore those paid results with voice search. With a screen, your eye can skip right over those ads in a matter of milliseconds. But with voice search, you’ll have to wait seconds to listen through an ad. Sure, we do it on YouTube and television. But we don’t like it. And we certainly won’t like it if we came to the digital assistant for a specific answer, not entertainment, and we still have to listen through an ad just to get an answer.

So how will search engines solve the paid search conundrum? With a screen, of course — only a virtual one.

Virtual and augmented reality — the screens of the future

There’s no doubt that the brain trusts at Google, Microsoft and Facebook have been thinking about this problem for a long time. There’s a reason that all of these companies are pushing hard into virtual and augmented reality.

With the exponential growth of connected devices hitting over 20 billion by the end of the decade, more users will expect to interact with their devices without a screen, fueling the rise of voice search. But we still need screens if Google and the others want to turn a profit. Otherwise, we won’t be able to rapidly process information to make our decisions.

The most likely solution will be to simply project a screen in virtual and augmented reality. This will allow you to visualize the map, or any other product or service you’re considering buying, only you’ll be doing it without ever touching a mouse or a screen.

In the short term, your smartphone screen will provide the same function as your future virtual screen. In the long term, expect to see augmented and virtual reality glasses to take your phone’s place. Don’t be surprised when you start seeing more products like Google Glass popping up.

Other solutions to the paid voice search conundrum include selling digital assistants as a service or these companies simply choosing not to monetize voice search and the map. The first option raises huge ethical questions about who gets access to digital assistants. The second option would be asking Google and Amazon to pass up a chance to make money. Neither is a likely alternative.

What should search marketers do?

Ads are coming to voice search sooner than you think. Last week, Amazon already started toying with the idea of selling ads on Alexa. Still, my advice for marketers is to begin optimizing for organic voice search. In the future, organic listings won’t go away; they’ll just be harder to earn.

Opinions expressed in this article are those of the guest author and not necessarily Search Engine Land. Staff authors are listed here.