Day shift supervisor: 'Job 1152 — drawing was revised, bore size changed. Changed at 2 pm. The job was supposed to run tonight but the night shift needs to know this before they start.' The supervisor leaves a note on the whiteboard. The note is legible. But the night shift supervisor comes in, reads the shift handover notebook, which is 10 pages and has thirty items, and misses the note about Job 1152. By 2 am, the night shift has cut 40 parts with the wrong bore size.
This happens at least once a week in a shop that runs multiple shifts. A change that lands on day shift doesn't make it to night shift. A breakdown on night shift doesn't get communicated to day shift so they plan as if it did not happen. A supplier call comes in — the second half of an order will be late. But it only gets to the day shift planner, and the night shift tries to run a job without half the material.
Why shifts are silos
Each shift has its own supervisor, its own problems, its own reality. The night shift does not have access to the email that came in during the day. The day shift does not hear about the spindle problem that the night shift discovered. Information flows within a shift but dies at the handover.
The handover is a few minutes of conversation plus a notebook entry. That is not enough time or bandwidth to convey all the changes that accumulated during the previous shift.
So the night shift makes decisions based on the plan as of 5 pm. By 6 pm, the plan has changed three times, but the night shift does not know. The night shift is executing obsolete information.
The cost
A shift that is executing the wrong plan makes waste. The job gets cut wrong. Material is used that should not be used. Rework happens, or scrap happens, or the job is delayed because the batch had to be rerun.
The cost looks like extra machine time, scrap, and delays. But it is rooted in a communication gap. The shifts are not talking. The shifts are not synchronized.
Multi-shift planning needs a shared view
- Every change lands in one place, visible to all shifts before any job based on that change starts running
- A change at 2 pm is on the night shift plan before the night shift arrives
- A breakdown on night shift is known to day shift before day shift starts planning
- The handover is confirmation, not discovery — the night shift knows what changed because they saw it in the system
Running three shifts without a shared information system is running three separate factories. They are not synchronized. They are not talking. And the customer feels all three of them missing their shipment dates.