Kary Mullis inventor of PCR test said they weren’t to be used for diagnosis. Hence, the tests were flawed and showed mostly false positives. This was done on purposely.
Didn’t quite achieve a false but made misleading
https://www.reuters.com/article/uk-factcheck-pcr/fact-check-inventor-of-method-used-to-test-for-covid-19-didnt-say-it-cant-be-used-in-virus-detection-idUSKBN24420X