Lesson 2: Design for the day the model is wrong
18 min read·13 Oct 2026
Module 14 · Lesson 2 · About 40 minutes · Needs: Module 8 Lesson 2 (the approval gate), Module 10 Lessons 1, 3 and 5 (the promise check, batch plans, online signals)
The situation
It is Monday 31 August 2026, week 14. Drafted replies for billing and sign-in tickets are going live behind a feature flag, and Maya wants the design checked before the flag widens. She brings one record. On 11 August Ravi approved a German draft, T-1187, that promised Brandt Logistik's admin a full refund 30 days after renewal. It was draft 31 of 40, reviewed in 25 minutes.
Joel's approval step stopped the money. Nothing stopped the words. This lesson follows T-1187 through six design decisions.