Manufacturing ERP systems plan production against theoretical equipment capacity rather than actual OEE because MES, SCADA, and ERP data remain siloed in incompatible formats, costing manufacturers 20-30% of revenue

Most discrete and process manufacturers operate with a fundamental disconnect between their Enterprise Resource Planning (ERP) system (which schedules and promises delivery dates) and their actual shop-floor performance (tracked in MES and SCADA systems). ERP systems plan against theoretical capacity -- for example, assuming a production line runs at 85% OEE -- when actual OEE may be 65% due to unplanned downtime, changeover delays, and quality losses. Because MES, SCADA, and ERP systems use different data models, communication protocols, and update frequencies, real-time reconciliation is impractical without expensive custom integration. The result is that sales teams promise delivery dates the factory cannot meet. Why it matters: production plans based on theoretical capacity systematically over-promise throughput, so orders are late and expediting costs spike, so customer satisfaction drops and contract penalties accumulate, so operations teams compensate by carrying excess WIP and safety stock (tying up 15-25% more working capital than necessary), so manufacturing executives cannot identify which capacity investments would actually increase output because they lack accurate, real-time bottleneck data, so capital allocation decisions are made on gut feel rather than data. The structural root cause is that ERP systems (SAP, Oracle) were designed around financial and material planning workflows in the 1990s with batch-update architectures, while MES and SCADA systems evolved from real-time process control with entirely different data models, and 30 years of acquisition-driven vendor consolidation has produced product suites that claim integration but actually wrap incompatible legacy systems behind unified GUIs without true data-model unification.