Quality control investigator: Upon testing samples of products from our supplier that were sent by our field inspectors from various manufacturing locations, our laboratory discovered that over 20 percent of the samples were defective. Since our supplier is contractually required to limit the rate of defects among items it manufactures for us to below 5 percent, it has violated its contract with us.
The quality control investigator's argument is flawed because it presumes, without providing justification, that the field inspectors were just as likely to choose a defective item for testing as they were to choose a nondefective item.