What happens when one places investment, R&D and manufacturing on the wrong technology? German automakers are about to find out. They are all-in for diesel engines at a time when the rest of the world is looking into electric. They have staked their reputations on diesel and come up short. Now they are facing a catch-up game in Europe and elsewhere as one country after another places the motor in the polluting column. It didn’t have to be this way. German car builders cheated to make the diesel meet air pollution standards, and they were caught. Now, they have to further refine the engine’s technology to pass muster or they will have to give it up for good. That is a tough choice, but their place in the market and their sales depend on it.