Often, several activities may have the same root cause For example, the costs of inspecting incoming components (output measure number of inspection hours) and reordering (output measure number of reorders) may both be caused by poor quality of purchased components. By working with carefully selected suppliers to help them their product quality, both activities may be improved. Typically, root causes ntified by asking one or more "why" questions. Example: Why are we inspecting incoming components? Answer: Because some may be defective. Question: Why are w components? Answer: Because some components are judged to be defective by the inspection. Question: Why are some purchased components defective? Answer: our suppliers are not providing reliable components. the answers to the wly ons are obtained, then the answers to "how" are Example: do we improve the quality of incoming components? By questions identified suppliers that provide higher-quality components. The why ways the root questions enable management to identify improve. causes, and the how