The Early 20th Century
The beginning of the 20th century marked the inclusion of “processes” in quality practices.
A “process” is defined as a group of activities that takes an input, adds value to it and provides an output, such as when a chef transforms a pile of ingredients into a meal.
Walter Shewhart, a statistician for Bell Laboratories, began to focus on controlling processes in the mid–1920s, making quality relevant not only for the finished product but for the processes that created it.
Shewhart recognized that industrial processes yield data. For example, a process in which metal is cut into sheets yields certain measurements, such as each sheet’s length, height and weight. Shewhart determined this data could be analyzed using statistical techniques to see whether a process is stable and in control, or if it is being affected by special causes that should be fixed. In doing so, Shewhart laid the foundation for control charts, a modern–day quality tool.
Shewhart’s concepts are referred to as statistical quality control (SQC). They differ from product orientation in that they make quality relevant not only for the finished product but also for the process that created it.
W Edwards Deming, a statistician with the U.S. Department of Agriculture and Census Bureau, became a proponent of Shewhart’s SQC methods and later became a leader of the quality movement in both Japan and the United States.