also you only need a confidence of 1 (as long as you did not submit this result)
So this leaves a false negative chance, and the odds against this are quite huge
Another possibility, though I don't know how likely this is: If there is a flaw in the glass master for a CD such that multiple copies have exactly the same incorrect data, then the rips will be verified by AR.
In addition, defective drives and issues with the ripping software can result and in all reasonable certainly have resulted in the population of the AR database with hashes for errant rips.
You're misunderstanding. By defective I meant a flaw in the design that may affect an entire line of drives sharing common firmware. I hope the software portion of my comment doesn't need similar qualification.
This is an old conversation which I'm really not interested in having yet again. I've analyzed tens of thousands of rips for myself and on the behalf of others and have seen my share of anomalies. So have fun blindly guessing at probabilities.