What's the point of concept cars?

The automakers spend millions to design and handbuild them and once the public sees them and gets excited over them the manufactures promptly take the concept car back to a museum someplace and no matter how much excitment they caused in the buying public---they don't get built. If they do, they're so watered down and re-designed by the time they hit production, that they rarely even resemble the concept cars we saw. I worked for Ford for 30 years and never did understand that waste of money.