As these examples show, instead of creating artificial testing environments disconnected from reality, we’re better off observing customer behavior in real life. If you want to design a better newspaper, watch people read the paper. If you want to design a better kid’s toothbrush, watch kids brush their teeth. If you want to see if people will love the iPhone, put an iPhone in their hands. “If you want to improve a piece of software,” as IDEO’s founder David Kelley explains, “all you have to do is watch people using it and see when they grimace.”45
