How I cleaned up OEE downtime reason codes that hid the real bottleneck

I ran into this in a packaging line where operators selected downtime reason codes on a touchscreen. The issue was OEE reports showed generic downtime as the largest category, so supervisors could not choose a real improvement project. At first I blamed operators being careless with data entry, but it showed up whenever the line stopped during changeovers and short material waits. This caused…