Which variation is described as resulting from how a process is designed to operate?

The variation that is described as resulting from how a process is designed to operate is common cause variation. This type of variation is inherent to a process and arises from the natural fluctuations that occur within standard operating conditions. It reflects the consistent, predictable, and stable pattern that occurs due to the design and inherent characteristics of the process itself.

Common cause variation essentially represents the baseline level of performance that can be expected from a process when it is functioning as intended. It is important for quality improvement initiatives because recognizing this type of variation helps organizations understand that any improvements aimed at the overall performance of the process must address the design and standard operating conditions. This contrasts with other types of variations, such as special cause variation, which stems from specific, non-routine events or changes that cannot be consistently expected. Thus, focusing on common cause variation allows teams to make systemic improvements rather than addressing isolated incidents.