Quite a while back, in 2020, Elon Musk spoke about being tested for Covid. He took 4 tests, all on the same day, and all from the same batch of testing devices. 2 were positive, and 2 were negative. They then decided to go with "positive". Very "scientific", eh? Flipping a coin gives you the same odds. And the CDC calls this PCR Test the "gold standard of Covid testing"
I know a married couple. He had no symptoms, but tested positive. She had symptoms, but tested negative. So, what was going on? Was he the Covid carrier and she had the flu? Or were both Covid carriers, or none of them?