Eight months ago, Snapchat, the well-known social network whose messages disappear within seconds, like bubbles in soda, raised money for the first time. Investors gave it around thirteen million dollars, estimating its worth, on paper, to be around seventy million dollars. A few months later, in June, it raised another sixty million dollars; its valuation had increased to eight hundred million dollars. Last month, Kara Swisher reported on the tech site All Things D that Snapchat might receive a pile of venture cash so large—two hundred million dollars—that its valuation would be pushed to around four billion dollars, a rather large sum of money to attribute to a company that has not, does not, and will not, in the immediate future, generate revenue. Some observers were apoplectic. Then, recently, it turned down three billion dollars, in cash, from Facebook.

How does a company that makes precisely zero dollars turn down multiple billions of dollars in cash? Perhaps because Snapchat’s founders, Evan Spiegel and Bobby Murphy, do not want to work for Mark Zuckerberg, whose company seems increasingly like any other incumbent: large, inert, uninteresting, and particularly boring to teen-agers, who even Facebook admits are fleeing the service. If every tech startup believes it can be the next Facebook or Twitter—or rather, the company that future startups aspire to be, one that fundamentally alters the way that a significant, if privileged, chunk of humanity conducts some everyday aspect of their lives—what’s a more direct admission of failure than becoming just another Facebook acquisition? It means, by definition, that your world-changing company is not so world-changing; in fact, it means, by every single metric, it’s worth less than Facebook. Snapchat and some of its supporters believe it is in the grander category: Steve Cheney, the head of business for GroupMe, a group texting service that was acquired by Skype, tweeted that Snapchat is “a new behavior and there will be no 2nd place.” In other words, not only is ephemeral social media destined to become a fundamental, lasting phenomenon—on par with a tweet or a “like”—but only one company will own it. This is the most ambitious reason to turn down three billion dollars.

The more straightforward and more likely answer is that the people who have determined its worth, its investors, believe it should get more. In the New York Times, Jenna Wortham reports that one of Snapchat’s initial investors, Benchmark Capital, was also an early investor in Instagram, and “was disappointed when Instagram’s founders decided to sell to Facebook for $1 billion last year.” Indeed, while Instagram’s price tag was once viewed as a ridiculous sum, the increasingly conventional view in Silicon Valley is that Instagram sold itself too soon, and for too little. Snapchat’s investors want more.

How much more? The latest, shakiest rumor is that Snapchat also spurned four billion dollars from Google, after instigating a bidding war of sorts. Perhaps five billion would be sufficient to sway Snapchat’s founders and investors; it’s the low end of what some investors believe Instagram is worth now. For however many billion dollars, a buyer would receive, in terms of hard assets, a small team of employees, some servers, an insignificant amount of real estate, and Snapchat’s technology, which is so basic, relatively speaking, that after its first rebuffed offer to acquire Snapchat around a year ago, Facebook effortlessly ripped it off wholesale. Of course, the value of these assets is much closer to zero than even a billion dollars. Rather, some odd billions of dollars is the price of the attention of Snapchat’s users, to whom perhaps advertising can one day be sold. Attention is the real currency of social-media companies, and it can be mercilessly capricious, particularly among the most coveted demographic of all, youth. One of Snapchat’s investors, Institutional Venture Partners, is quite explicit that it invested in a zero-revenue company because its “growth and engagement metrics are off the charts,” and because it is used largely by the young.

The question, then, is less why Snapchat is able to turn down three billion dollars than why and how attention has come to be so valuable, and if it will continue to be. Other companies attempted to acquire Facebook, Twitter, and Instagram, of course, but for smaller amounts of money. Is the quantity and quality of attention that Snapchat commands now—and potentially will command—actually more valuable? And will Snapchat’s audience continue to pay attention to it? Maybe. But to many, ten seconds at a time seems like an unlikely way to build a lasting empire.

Photograph by J. Emilio Flores/The New York Times/Redux.