In Who Do You Want Your Customers to Become?, a 76-page e-book from Harvard Business Press, Michael Schrage argues that the products we choose — be they smartphones, beverages, or airlines — leave powerful marks on us. They refashion us, whether we realize it or not.

In a post-Siri world, we find ourselves talking to a telephone … with no one on the other end of the line. In a Starbucks universe, ordering a cup of joe becomes an act of linguistic gymnastics and — all too often, during rush hour — supreme patience.

According to Schrage, a former Fortune columnist and a research fellow at the MIT Sloan School’s Center for Digital Business, companies like Apple (AAPL), HTC, and Samsung are not merely offering shiny glass screens that double as computers and telephones. “Their innovations are training their customers to behave — not just think — different.”

Schrage has a point, but I think he oversells it. Walk down any city street or office hallway, and you’ll surely spot at least a few poor saps tottering along with their faces glued to a handheld screen (I’ve certainly been one of them, err, this week.) While he’s right that modern screen culture encourages compulsive behavior, the fact is that human obsessive tendencies predate 21st century consumer electronics.

Schrage asks his audience of business readers to design products that customers might want to use. He also implores them to determine exactly who they want their customers to become, referring to this company-to-customer request as The Ask.

“The real purpose of business is to profitably transform a customer,” Schrage writes. In this sense, products shouldn’t simply be commodities, he argues. Instead they should border on art. This idea recalls a passage in The Gift, a classic work by literary critic Lewis Hyde: “The greatest art offers us images by which to imagine our lives.” But once that piece of art enters the market, Hyde argues, it loses some of the qualities that made it so powerful to begin with.

An iPad might seem magical to many of us, but does it really help us re-imagine our lives in new ways? That’s a hefty mandate for any company, even an Apple. Speaking of Apple, Steve Jobs was perhaps the grand poobah of this business approach. “Jobs wanted customers to become as design-obsessed and detail-oriented around digital technology as he was,” Schrage writes. “Apple trained its customers to become design connoisseurs.”

Schrage presents case studies of several customer-transforming companies and lays out common elements in their strategies. For one, they invest time and energy in training their customers to know and use their products. Discount fashion retailer Syms turned this strategy into a marketing slogan: “An Educated Consumer is Our Best Customer.” And Google (GOOG), Schrage argues, trained a generation of searchers to accept fewer search results on each page in exchange for faster delivery, even if they claimed they wanted the opposite (more result on each page, albeit at a slower pace). The idea is that this training eventually pays off because smarter customers are ultimately more valuable customers.

Customer-focused companies also make sure that their users don’t have to jump through too many hoops in order to change. “Simpler is better than complicated,” Schrage writes. “Faster is better than slower. Responsive is better than resistant. Easier is (much) better than harder.”

Fair enough. This sort of thinking assumes, however, that buyers are like clay, ready and willing to be molded if the product is shiny enough. Steve Jobs epitomized this attitude. In an interview with Fortune, Jobs said: “One of the keys to Apple is that we build products that really turn us on.” Focus groups and market research be damned, it’s about what we want! Yet customers, American ones anyway, like to think of themselves as independent actors. Maybe we’re naïve, or maybe we retain the illusion of agency because the companies want us to. Still, we believe that we chose that cup of coffee, that car, that smartphone because they fit our needs. We change because we want to change, not because some profit center has engineered us into a new state.

Successful customer-company relationships are not just about who companies want their customers to become, but also who customers are willing to become, and what they want companies to become. If you train us to pay one flat fee for DVDs-by-mail and streaming movies, then suddenly separate those two businesses and ask for more money with no additional benefits, you’ll run into problems. (Here’s looking at you, Netflix (NFLX)).

It’s great to create products that you love, but you’d better make sure that others will love them too, otherwise you’re just pursuing a hobby on the company dime. (See under: Apple TV). And while few corporate leaders lack hubris, even fewer have Jobs-level design and marketing chops. Schrage admits this, warning that not everyone can be a DIFY (Do-It-For-Yourself) entrepreneur. He writes: “If you cannot be your own best customer … you have no choice but to become even more customer-focused, customer-centric, and customer-aware.”

To his credit, Schrage devotes considerable space to the risks involved in asking customers to change. McDonald’s (MCD) may have wanted to make an easy buck by urging its customers to supersize their meals, but they didn’t exactly prepare for the result: supersized customers.

Companies can’t determine what their customers ultimately become. That never stopped any company from trying, though. Business leaders like to imagine that they have the awesome responsibility of guiding their customers’ life paths. (Coming soon: Holy Church of Apple?). It’s not that simple, though. Behemoths like Google, Microsoft (MSFT), and Starbucks (SBUX) have changed our behavior and, in turn, the way we live. But so have myriad other forces, from the macroeconomic to the social, the political, and the artistic. In the end, consumer products are just stray vegetables in a very large bowl of soup.