DBA Manufacturing does not include any shortage reports because manual planning from shortage reports is counter-productive and incompatible with the scheduling system. Inefficient manual planning is replaced by Time to Shipment MRP.
Manual planning from shortage reports is counter-productive
Manual planning from static shortage reports is counter-productive because it fails to account for the time-phased nature of demand, which means that items are often made or purchased far earlier than needed. It also fails to account for the progressive nature of lowest-level BOM demand creation whereby demand at one level generates demand for subassemblies and materials at subsequent levels. Manually created jobs and purchase orders lack proper date alignment and don’t reflect the correct order of assembly for job release or coherent required dates for prioritized production. Manual planning is highly vulnerable to human error and prone to shortages and over-stocking.
Manual planning from BOM explosions is counter-productive
Shortage reports based on BOM explosions isolate demand into inefficient product structures that fail to take into account interdependent demand from other items. This type of planning results in fragmented schedules with excessive numbers of inefficient jobs and purchase orders and discourages strategic stocking of key subassemblies and materials to reduce lead times.
Time to Shipment MRP replaces inefficient manual planning
None of these flaws and inefficiencies exist with Time to Shipment MRP, which replaces manual planning. Item Lead Days and Job Days allocations and strategic assignment of Stocking order policies establish realistic Time to Shipment targets for top level items. Jobs and purchase orders are generated in a time-phased, multi-level progression in response to current, interdependent demand that needs action now. Scheduling dates are properly aligned in the correct order of assembly and with meaningful job prioritization. MRP is foolproof because it is impossible for any demand to fall through the cracks and not be actioned upon.