Why Your BOMs Drift — and What It Costs
5 min read
Revision control, substitutions and engineering change: how bills of materials lose accuracy and what that does to planning.
Bills of materials rarely fail all at once. They drift: a substitution made on the floor during a shortage, a fastener quantity that was never corrected, a revision released in engineering but not reflected in planning.
Each small inaccuracy compounds through MRP. Understated quantities create shortages that look like supplier failures. Obsolete components stay in the plan and get purchased. Costing drifts, and quoting drifts with it.
Controlling drift requires a defined change path — who can change a BOM, what triggers a revision, how effectivity is recorded — and a where-used view so the impact of a component change is visible before it is made.