John McElroy:

To paraphrase Elon Musk, Silicon Valley is learning that “Making rockets is hard, but making cars is really hard.” People outside of the auto industry tend to have a shallow understanding of how complex the business really is. They think all you have to do is design a car and start making it. But most startups never make it past the concept car stage because the move to mass production proves too daunting. Even Tesla, the only successful automotive company to come out of Silicon Valley so far, made but 80,000 cars last year and it’s been in business for nearly 15 years.