Technology products that want mass adoption should be designed for novice users. ”Normals” as Chris calls them. Products need to be blindingly simple. You take your User Persona and try to see the product through their eyes, not yours. You then invite people who match this User Persona and watch them use prototype of your product. There is only one way to really know whether you’ve achieved product nirvana: film users playing with your product and watch them interact with it. I’ve seen this many times first hand and even your best attempts at designing “simple” products will surprise you when you see Normals trying to use them.