Ask Apple CEO Steve Jobs about it, and he’ll tell you an instructive little story. Call it the Parable of the Concept Car. “Here’s what you find at a lot of companies,” he says. “You know how you see a show car, and it’s really cool, and then four years later you see the production car, and it sucks? And you go, What happened? What happened was, the designers came up with this really great idea. Then they take it to the engineers, and the engineers go, ‘Nah, we can’t do that. That’s impossible.’ And so it gets a lot worse. Then they take it to the manufacturing people, and they go, ‘We can’t build that!’ And it gets a lot worse.”