Question
Decide whether the error was a slip or a mistaken plan
Forgetting a correct step and confidently choosing the wrong step are different failures.
When it fits
- A failure triggers the automatic response 'train the person again.'
When to avoid it
- Do not use the labels to excuse reckless behavior or to infer someone's mental state without evidence.
A question to ask
An expert knew the correct sequence but skipped one familiar step after an interruption. What class fits first?
Why it matters
Ask whether the person knew the correct action but failed to execute it, or whether their model of the situation led them to choose the wrong action. Treat slips with memory, interface, distraction and workflow design. Treat mistakes with better information, training, supervision or decision support. Mixed cases can need both.
An example
Typing the correct customer ID into the wrong field is different from believing the wrong customer should be updated.
Check your result
The corrective action targets the type of failure that actually occurred rather than defaulting to retraining.
Keep this limit in mind
- Do not use the labels to excuse reckless behavior or to infer someone's mental state without evidence.
Connected ideas
Useful withRedesign a repeat slip before scheduling more training
Evidence and sources
Human-factors guidance distinguishes slips or lapses in routine behavior from mistakes in active problem solving because their prevention strategies differ.
Real incidents can involve both a slip and a mistaken plan.
Systems Approach · Developing Solutions for Active and Latent Errors