There is a counter argument to refurb parts that one does not have to agree with, and the legal system does not but.
If you have a 100% new part it has been tested. Sometimes the test itself is enough to degrade or cause a premature failure if the part is marginal to begin with. The new part could last days or forever. Most people are comfortable with new because it is new, and because most things have DOA return/replace, no hassles, and things are normally reliable.
OTOH, a refurb could be a working part harvested from a product that had a failure unrelated to that part, which has now been burnt in for reliability and tested, or it could be a part that had failed, was repaired and tested, OR never properly repaired because they only fix the symptom and rarely if ever look for the underlying cause. For example a bad power supply could keep damaging various electronics and the electronics will be replaced/repaired but the power supply problem will never be noticed while the product will continue to fail. (This is often the real problem with single unreliable TVs - they will keep changing out a failed module but the power supply will keep damaging them.)
Luck of the draw, a refurb part might be as good or better than a new one but sometimes pretty ordinary or worse.
After many years of dealing with large exotic systems I found the best outcome for contract price and performance (reliability) was letting the supplier repair with whatever he wanted, as long as it was warranted as if new. Catching the real problem when it wasn’t the symptomatic one was achieved by requiring any unit be replaced if it had a repetitive fault in an FRU (field replaceable unit, eg the replaceable part); that would catch a faulty power supply, for example.
It would be interesting if this method could be applied to consumer goods.
