What is the target number of defects per million that companies should aim for according to Smith's belief in Six Sigma?

In the context of Six Sigma, the target number of defects per million opportunities that companies strive for is 3.4. This figure reflects the philosophy of achieving near perfection in processes, meaning that for every million opportunities for a defect to occur, only 3.4 defects should be present at most. This standard is derived from the statistical concept of a Six Sigma process, which represents a process operating at a quality level of 99.99966%.

This emphasis on 3.4 defects per million opportunities illustrates the commitment to minimizing variability and improving quality to an exceptional level, ultimately leading to higher customer satisfaction and reduced costs related to rework and defects. This benchmark is widely used across industries striving for operational excellence and is a critical metric in Six Sigma initiatives.