Five Whys

Five Whys is a questioning technique that moves from a stated problem to more specific explanations by repeatedly asking why it occurred. The number five is a prompt to look beyond the first answer. It does not require exactly five questions or certify the final answer as a proven cause.

For a damaged-delivery complaint, a team might ask about physical damage, movement inside the box, padding practices, staff preparation, and the controls governing independent assignment. Each answer is a candidate connection until observations or records support it. If delivery handling rather than packing explains the damage, continuing down the training branch would investigate the wrong mechanism.

Write the evidence, uncertainty, and next check beside each answer. Ask what would contradict it and involve people who see different stages of the work. Stop and investigate when an answer is unsupported; split the analysis when several causes could contribute. Do not force a chain to end at a person or department.

The technique helps organize investigation but does not replace a timeline, process analysis, or a suitable test of an intervention. Agreement among participants is not independent evidence. After choosing an action, check both whether it was implemented and whether the relevant outcome changed under comparable measurement conditions.

Reference: ASQ: Five Whys. Examples are illustrative.