Case context: A warehouse inspection system has three stages: Package Scanning (A), Damage Classification (B), and Dispatch Routing (C). On one dev-set case, the system assigns the wrong route. You substitute a flawless output for Package Scanning (A), but the route is still wrong. You then substitute a flawless output for Damage Classification (B), and the route becomes correct.

Question: Using the general error attribution procedure, which stage should the engineer blame for the incorrect routing on this dev-set case, and why?

Sample answer: The engineer should blame Damage Classification (B). The attribution procedure says to test stages in order: if a perfect output for A does not correct the outcome, continue to B. In this case, fixing A alone did not solve the routing error, but fixing B did. That means the system would have produced the right result if B had been better on this example, so B is the source of the mistake.

Key points:

• Stage B (Damage Classification) caused the error.
• A perfect output for A was not enough to correct the system.
• A perfect output for B made the overall output correct.

Rubric: The response must name stage B (Damage Classification) as the error source and explain the choice using the logic of the attribution procedure.