“Growing legions of marketing consultants are pushing social media as the can’t-miss future. They argue that pitches are more likely to hit home if they come from friends on Facebook, Twitter, Tumblr or Google+. That’s the new word of mouth, long the gold standard in marketing. And the rivers of data that pour into these networks fuel the vision of precision targeting, in which ads are so timely and relevant that you welcome them. The hopes for such a revolution have fueled a market frenzy around social networks — and have also primed them for a fall. …

For generations, Mad Men had thrived on widespread trust that their jingles and slogans altered consumers’ behavior. Thankfully for them, there was little data to prove them wrong. But in an industry run remorselessly by numbers, the expectations have flipped. Advertising companies now face pressure to deliver statistical evidence of their success. When they come up short, offering anecdotes in place of numbers, the markets punish them. Faith has given way to doubt.

This leads to exasperation, because in a server farm packed with social data, it’s hard to know what to count. What’s the value of a Facebook “like” or a Twitter follower? What do you measure to find out? …

“It’s hard to measure influence,” says Steve Canepa, I.B.M.’s general manager for media and entertainment.

That, in fact, may be the ultimate lesson to draw from the social media marketing miracle that wasn’t. The impact of new technologies is invariably misjudged because we measure the future with yardsticks from the past.

Dave Morgan, a pioneer in Internet advertising and the founder of Simulmedia, an ad network for TV, points to the early years of electricity. In the late 19th century, most people associated the new industry with one extremely valuable service: light. That was what the marketplace understood. Electricity would displace kerosene and candles and become a giant of illumination. What these people missed was that electricity, far beyond light, was a platform for a host of new industries. Over the following years, entrepreneurs would come up with appliances — today we might call them “apps” — for vacuuming, laundry and eventually radio and television. Huge industries grew on the electricity platform. If you think of Apple in this context, it’s a $496 billion company that builds the latest generation of electricity apps.

Social networks, like them or not, are fast laying out a new grid of personal connections. Even if this matrix of humanity sputters in advertising and marketing, it’s bound to spawn new industries in consulting, education, collaborative design, market research, media and loads of products and services yet to be imagined. Maybe, just maybe, it will even be able to sell soap.”