In lean Manufacturing, which term describes fluctuations in process performance (uneven)?

In lean Manufacturing, which term describes fluctuations in process performance (uneven)?

• A. Uncaptured or measured waste
• B. Muda
• C. Muri
• D. Mura

Answer: (D)

Fluctuations in process performance, meaning an uneven pace of production and varying workload across steps, are described by Mura. When work arrives or is produced at inconsistent rates, different parts of the process must idle or rush to catch up, leading to stoppages, overtime, and larger inventories as buffers form to absorb the variability. This unevenness hurts flow and makes lead times unpredictable, which is exactly what Lean aims to prevent by leveling production and smoothing workload. Muda is the waste that results from activities that don’t add value, Muri is the overburdening of people or equipment, and Mura is the irregularity that triggers those issues. So the term that best captures the idea of uneven, fluctuating performance is Mura.

Fluctuations in process performance, meaning an uneven pace of production and varying workload across steps, are described by Mura. When work arrives or is produced at inconsistent rates, different parts of the process must idle or rush to catch up, leading to stoppages, overtime, and larger inventories as buffers form to absorb the variability. This unevenness hurts flow and makes lead times unpredictable, which is exactly what Lean aims to prevent by leveling production and smoothing workload.

Muda is the waste that results from activities that don’t add value, Muri is the overburdening of people or equipment, and Mura is the irregularity that triggers those issues. So the term that best captures the idea of uneven, fluctuating performance is Mura.