Every manufacturer has experienced it. A successful kaizen event produces measurable results — reduced changeover time, improved OEE, fewer defects. Within 90 days, performance drifts back toward baseline. The improvement was real. The sustainment system was not. The root cause is not a lack of Lean knowledge. It is a lack of daily management infrastructure. Standard work exists in binders that operators do not reference. LPAs are conducted sporadically or not at all. Tier meetings happen, but without structured escalation, issues raised on Monday are still unresolved on Friday. Corrective actions open and never close. McKinsey's research on Lean management found that 70% of continuous improvement programs fail to sustain their gains beyond 18 months (McKinsey, "The Lean Management Enterprise," 2014). The Lean Enterprise Institute's own studies indicate that standard work adherence in most plants averages 40-55% — meaning nearly half of documented best practices are not being followed on any given shift (LEI, 2019). This is not a training problem. It is a systems problem. CI programs sustain when the daily management system enforces adherence, surfaces deviation, and drives accountability. Without that system, every improvement event is temporary.