A concrete challenge for Dru’s ‘throw away discovery code’ rule—but only at the *personal UI* scale: Ben Thompson asked Muse to sort his Instagram recipes, rejected its first PDF, and had a usable private browsing interface about five minutes later. He calls such interfaces disposable; that is not evidence that a team should ship prototype code or that the app survives a month of use. The change of format came from actually trying the first result.