Belief builds products, and objectivity gets them bought. I recently worked with an inventor developing really cool new product. Let’s call it a compact water filtration system, to protect the guilty. Who in this case is a really nice guy. Smart. Capable. Utterly convinced the market was gi-normous. His math was ambitious. Three billion possible buyers worldwide. Everyone and their dog drinks water. Everyone needs cleaner water. Therefore, EVERYONE with a wall plug-in might become a customer....