Think about a product's life span. When something new is released to the public—and this is especially true of software—it's hardly set in stone. You get feedback from customers and make modifications. You add features, refine existing ones, and make things better over time. If you really listen and do it right, the product earns its success. But paradoxically, that success makes it harder to change. As time goes by, people get used to things the way they are. And the more someone is accustomed to doing something a certain way, the harder it is to ask him or her to change. When it comes to introducing ideas, the years have a way of boxing you in.