The pitch was impressive. AI tools would make developers faster, reduce headcount costs, and pay for themselves many times over. Companies that moved early would have a structural advantage over those that waited. Microsoft believed it. So did Uber. Both pushed hard on AI coding tool adoption across their engineering teams. Both are now dealing with same problem: the faster their employees embraced the tools, the faster the bills grew. In some cases those bills have started exceeding what the same work would have cost with human labor. The problem is what happens to the economics when thousands of employees use something that charges per unit of thought.