For that reason, the workplace was strongly affected by the works of Frederick W. Taylor, who was regarded as the Father of Scientific Management.
The workforce consisted first of immigrants and farm workers who knew nothing about the machinery they were supposed to handle. Taylor suggested that engineers design the work and standardize tools and procedures. Workers were only expected to perform their assigned work and the quality of their work was the responsibility of the inspector. Also, large tasks were broken down into smaller ones, which gave way to a high degree of specialization. This task specialization lead to the introduction of the assembly line.
The costs of moving material from one operator to another were getting higher. For this reason, Henry Ford decided the automate the material-handling task by introducing the assembly line, and by doing this he reduced the cost in 1990 from $12,000 to $2,100.
As products became more complex, the checking dimensions performed by inspectors required more sophisticated measuring tools. In 1920's the inspection activities were declared as a formal quality function. Quality control was responsible for developing tools to check product dimensions and characteristics, detecting errors, and having the necessary rework be performed. It was assumed that the only way to ensure good quality was to inspect all the items performed.
When Walter Shewhart was hired as a quality control inspector for telephones, he suggested using statistics as a way of reducing the amount of inspection. Instead of checking the entire lot, only a sample would be checked, which means that the costs of inspection will fall. Although performing this procedure gives way for a very small percentage of defects to be shipped, but the savings in inspection costs of inspection will fall. This average defect rate was called the Average Ongoing Quality Level (AOQL).
Shewhart also pointed the importance of process control.
