What technique did Walter Shewhart devise?

Walter Shewhart is known for developing Quality Control Charts, which are essential tools used in statistical quality control. These charts help visualize data over time, allowing teams to monitor process stability and identify variations in manufacturing and service processes. By using these charts, organizations can distinguish between normal process variations and those that indicate problems that require investigation.

Quality Control Charts became foundational in the field of quality management, helping industries implement more rigorous quality control measures. This technique supports the continuous improvement process, which is a key principle in Lean Six Sigma methodologies. As such, the development of Quality Control Charts by Shewhart has had a lasting impact on quality assurance practices across various sectors.

The other options, while related to quality improvement and management, do not specifically pertain to Shewhart's contributions. Six Sigma analysis is an approach that comprises various tools and techniques developed later, root cause analysis is a problem-solving method that gained prominence in the mid-to-late 20th century, and benchmarking strategies involve comparing processes and performance metrics to industry bests, which are not attributed to Shewhart’s work on statistical process control.