There is a scheduler somewhere in your operation whose spreadsheet is the real plan. Not the one in the ERP. Theirs. It works because decades of judgement is encoded in the way they order the jobs. When they retire, that judgement leaves the building, and it does not appear anywhere in the handover document. Why the handover never works Knowledge that took decades to build cannot be transferred in two weeks of shadowing. What gets written down is the procedure. What matters is the exception handling, and the exceptions are the part nobody remembers to describe. The cost shows up late Output usually holds for a quarter. Then the new person hits a situation the procedure does not cover, makes a defensible call, and it is wrong in a way that only somebody with decades on the floor would have seen coming. By the time it shows up in the numbers, nobody connects it to the retirement.