It Is Usually Not Theft
When inventory comes up short, the first instinct is to suspect theft. But research consistently shows that the majority of employee-caused shrinkage comes from innocent mistakes, not dishonesty. Understanding the psychology behind these mistakes helps you design systems that prevent them.
Cognitive Biases That Cause Inventory Errors
Confirmation Bias
When a counter sees "Expected: 24" and looks at a shelf that appears to have about 24 items, they confirm 24 without actually counting. This is the single biggest reason blind counts are more accurate than open counts.
Anchoring
The first number an employee sees becomes an anchor. If the last count was 50, they expect approximately 50 this time and are more likely to count 48-52 even if the actual number is 43.
Fatigue and Attention Decay
Counting accuracy drops significantly after 90 minutes. By hour three, error rates can double. Short, frequent audit sessions (45-60 minutes) produce dramatically better results than marathon counting sessions.
Inattentional Blindness
When focused on counting one thing, people often fail to notice another. An employee counting blue t-shirts might overlook a blue t-shirt that was placed in the wrong section because they are focused on the section they were assigned.
System Design Failures
Ambiguous Processes
If your receiving process is "check the shipment and put it away," mistakes are inevitable. If it is "count every item against the invoice, sign the invoice, enter quantities into Clover, then shelve," errors drop dramatically.
Too Many Steps
Complex processes get shortcut. If updating inventory after receiving requires navigating through five screens, employees will "do it later" -- and later never comes.
No Feedback Loop
If employees never see the results of their counts -- never know whether their counts were accurate -- they have no motivation to improve. Sharing audit results (without blame) creates a natural improvement cycle.
Designing for Humans
- Use blind counts to eliminate confirmation bias
- Keep sessions short (under 90 minutes) to prevent fatigue errors
- Simplify processes so the right way is also the easy way
- Use technology (barcode scanning) to eliminate data entry errors
- Provide feedback so employees know how they are performing
- Rotate counters so fresh eyes catch what tired eyes miss
Good employees make mistakes because they are human. Good systems make mistakes hard to make. Design for the human, and accuracy follows.