Question: A warehouse robot pipeline includes two independent perception steps: one identifies package labels and the other checks shelf markers before route planning. Why can swapping the order of those two steps still leave the error analysis useful, even if the measured counts change a little? Discuss the directed-graph constraint and how this affects decision making.

Sample answer: If the two steps do not depend on one another, switching their order does not violate the workflow graph, because later stages still receive the outputs they need from earlier stages. The exact attribution numbers can shift slightly since failures may be assigned in a different sequence, but the comparison still points to the parts of the system that deserve attention. For that reason, the analysis remains useful for deciding where to spend development effort.

Key points:

• Swapping independent steps still respects the directed dependency structure.
• The numerical attribution can change a bit because the order of evaluation changes.
• The overall guidance for prioritizing improvements remains valid.

Rubric: The answer must mention that reordering independent steps preserves the directed dependency structure. It must explain that the numbers may shift because the evaluation order changes. It must conclude that the analysis remains valid for prioritizing work.