Why a Factory Makes a Big Batch Before Switching Products

A customer wants green cards. Why does the workshop keep printing blue? Follow a fictional card workshop through preparation, printing, waiting stock and product changeovers. The invented examples distinguish spreading setup time from speeding up a machine, then show how a hypothetical preparation improvement changes the comparison. Production batches and transfer batches answer different questions. All quantities and times in the card workshop are teaching assumptions, not measured factory results, equipment specifications or operating advice. The 40-to-5-minute change is hypothetical. Real improvements require qualified process controls, comparable records and unchanged safety and quality requirements. Chapters 00:00 Why not switch to green? 00:40 An imaginary workshop 02:20 Same output, different schedules 03:34 The customer has another clock 04:31 Forty cards awaiting demand 05:46 Queues and responsiveness 06:29 Improve the preparation 08:02 Change one assumption 09:33 Production batch versus transfer batch 10:35 Feedback and useful output Official sources https://www.lean.org/lexicon-terms/si... https://www.epa.gov/sustainability/le... Narration: Kokoro am_michael Visuals were newly generated for this video and are explanatory illustrations, not real records or actual measured plans.