Hmm. As a general rule I disagree with that. As an example, in the context of used OEM parts vs aftermarket with most auto parts.Never put a used part back in.
I lesson learned the hard way that almost cost me a trip to Balls and got me pulled over along the way to boot. All due to alternator that the NAPA guy tested and said was good.
Stupidest $80 I've ever "saved."