The point is that people who go to business school are taught that it is not desirable to simply sell a product once to a customer. They all want recurring revenue and look for ways to maximize that. And this changes the way in which products are designed.

Razor and blade is the default now, and it basically takes a customer revolt to move away from it. Even the pod coffee maker tried to RFID tag the pods so only "official" ones worked, and it took a customer revolt for them to back off on that idea.