Hit the target and reduce the variation. The aim of the Taguchi Loss function. back in the 1980's Ford found out how real this Loass function is at the Batavia transmission plant...
https://www.youtube.com/watch?v=uAfUOfSY-S0
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Design of Experiments for 21st Century Engineers - https://www.lulu.com/en/us/shop/paul-allen/design-of-experiments-for-21st-century-engineers/paperback/product-124en77d.html
Statistical Process Control for Small Batch Production - https://www.lulu.com/en/gb/shop/paul-allen/statistical-process-control-for-small-batch-production/paperback/product-7j9pde.html?page=1&pageSize=4