As a journalist, I make a living asking questions and listening to what people have to say. When I'm visiting manufacturers, one of the first things I ask about is what is their biggest headache. It's never too hard to get people to talk about what wakes them up at 4:30 in the morning, whether it's a 4-week-old baby or a new product launch about to come on line. How people respond to the question often reveals how much process improvement they've made. The responses tend to place manufacturers into four categories: