As we learned from New Coke, Pets.com, Apple's original handheld device, the Newton, and the reissued Ford Thunderbird, all the promotion in the world won't save a product that somehow isn't right. Robert Cooper is the world's leading expert on making sure your new-product introductions are more like Apple's iPods and less like Newtons. Cooper invented what's called the "stage-gate" process of new-product development-a process used by 60% of all businesses...