Might a pharmacy order more stock because of one unusual day?
Every trend begins as an exception.
One unusual day creates a forecasting dilemma.
The hidden mechanism is trend detection. Businesses continuously decide whether unexpected demand should be ignored or treated as a meaningful signal.
Imagine a pharmacy selling three times its normal volume of a product. The spike could be random. It could also be the first visible sign of changing demand.
A second-order effect develops because inventory decisions influence future outcomes. Overreacting creates excess stock. Underreacting creates shortages. Both mistakes generate new information that affects future forecasts.
People often think trends become visible when they are obvious. For inventory managers, the challenge is deciding when an exception has stopped being an exception.
