One idea I want to address here is called “Work in Process,” or sometimes just “inventory.” The idea is that it’s wasteful to have a bunch of stuff lying around that isn’t being used to build something. That stuff, whether it be car doors or widgets, actually costs money, and if it’s sitting around on the factory floor, it means that huge amounts of money are bound up in inventory that isn’t actually needed right then. This changes how you look at things that are in process.
