Which of the following terms is defined as the ratio of value-added time to total...

Process cycle efficiency is the Lean Six Sigma measure defined as the ratio of value-added time to total lead time. It indicates how much of the overall elapsed time is actually spent performing work that the customer would recognize as valuable, compared with time consumed by waiting, transporting, storing, inspecting, reworking, or other non-value-added activity. This makes it an important organizational process management measure because it highlights hidden waste inside a process. A high process cycle efficiency indicates that the process flow is relatively lean, while a low value signals that a large share of lead time is being lost to delays and inefficiencies. In Black Belt practice, this metric is often used with process maps and value stream analysis to identify opportunities for cycle-time compression and waste removal. The other options are not defined this way. Cycle-time reduction is an improvement objective, not the ratio itself, and return on assets or return on investments are financial metrics rather than flow-efficiency measures. Therefore, the correct answer is Process cycle efficiency.

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