A lot of things about Facebook’s latest earnings report are worthy of superlatives, including its 52% revenue growth, a profit that more than doubled, and the fact that the site has nearly one billion daily users. But even more incredible, if possible, is the fact that 80% of the company’s advertising revenue came from mobile.

This may not seem all that surprising—after all, mobile is rapidly taking over the digital world, and the growth rates of almost any service focused on the mobile market have been meteoric. So the fact that a lot of Facebook’s revenue comes from mobile makes sense.

The incredible part is the sheer speed with which Facebook FB has gone from being the underdog to being one of the most dominant players in mobile advertising, and in mobile media as a whole. And the way it did that has some lessons for media companies.

In 2012, Facebook was so mobile-challenged that it had to warn investors publicly via an SEC filing about its weakness in the mobile market. At the time, it hadn’t gone public yet, but it was preparing to do so, and it filed an amended prospectus saying it was struggling with mobile advertising and not having much success.

In the filing, the company said that it did not “directly generate any meaningful revenue from the use of Facebook mobile products, and our ability to do so successfully is unproven.” The network said it had tried inserting what it called “sponsored stories” into mobile Facebook feeds, but wasn’t having much luck.

By the end of 2012, Facebook’s mobile revenue was at 25% of overall revenue, and by the end of 2013 it was at 50% of revenue. Last year, less than four years after saying it was making nothing on mobile and wasn’t sure it ever would, Facebook booked more than $4 billion in mobile advertising revenue, or 80% of the total.

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Most traditional media companies, meanwhile—whose businesses are in many ways very similar to Facebook’s, since they also monetize their readers or users through advertising—continue to struggle with mobile. That’s why so many have chosen to partner with Facebook on its mobile “Instant Articles” feature: Because they know Facebook is much, much better than they are at serving up mobile articles and advertising.

Right now, anyone in the media reading this is probably thinking: “Well, of course Facebook went from zero to $4 billion in mobile advertising revenue. The company went public at a huge valuation, and has had money pouring through the doors ever since. We would all be killing it on mobile if we had that kind of cash and user base to exploit.”

That may be true, but it misses the central point, which is that user growth and lots of cash isn’t really what helped Facebook do what it did. It was a relentless and single-minded focus on getting mobile right—and in particular, getting it right for users, not getting it right for the finance or the advertising sales department.

Look at what Mark Zuckerberg said in response to a comment on the recent earnings call. As my Fortune colleague Erin Griffith describes it, an analyst mentioned a “billion-dollar conversation” that Zuckerberg supposedly had with the mobile team about all the money they were leaving on the table. Here’s what the Facebook founder said:

I don’t know where you got that story from. I never had a conversation with the engineering team, where we were behind on mobile and I said, “We need to do this to make money.” That’s not really how we operate. What happened was we realized mobile was growing faster than desktop and people were shifting their usage. It was the more important thing for people’s consumer experience.

That’s when we made the shift. Not in our business first, but in how we developed the products. I told all of our product teams, when they come in for reviews: “Come in with mobile. If you come in and try to show me a desktop product, I’m going to kick you out. You have to come in and show me a mobile product.”

Are there any CEOs or publishers at media companies who did anything even approaching what Mark Zuckerberg did? Who kicked their design or usability or revenue teams out if they came in with a desktop product and told them to come back with a mobile one? Unlikely. If they had, many would probably be a lot further down the road than they are.

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And yes, I know that newspapers and TV companies and other traditional media entities have existing legacy businesses to run, based in print or broadcast. But so did Facebook—it had a giant money-spinning machine based on the desktop, and yet it deliberately took the chance of cannibalizing that product to make mobile work.

Not only that, but Facebook did this first by focusing on the user, and what they might want or need—things like speed of loading, and ads that weren’t intrusive, etc.—not on generating revenue. What did publishers do? Spent all their time adding more slow-loading ads and popups and tracking widgets, until the actual content at the heart of the user experience was almost impossible to see or engage with.

No one is saying that media companies could have had Facebook’s growth rate, or $4 billion in mobile advertising, if they had only done this sooner. But they would undoubtedly be a lot farther ahead than they are now, and ironically, they probably wouldn’t have had to rely as much on Facebook for distribution as they do now. But that ship has sailed.