Dr.KarenChen said:Prices dramatically below market are the strongest single signal, and the reason is arithmetic rather than suspicion.
I disagree that testing history is decisive. It tells you what a supplier did when they were being watched. Continuity of behaviour under stress — a late shipment, a failed test, a complaint — is more predictive than any run of good results.
wendy_avl said:Eight months with one supplier, then a change in how they communicate that I noticed before I noticed anything about the product.
Shipping damage protocol for vendor vetting orders: if your package arrives with visible damage, temperature excursion, or broken vials:
Reputable vendors will replace damaged shipments without argument. If they push back, that's a red flag about the vendor.
DebRD_ATL said:I disagree that testing history is decisive.
Coming at DebRD_ATL’s question from a different direction. The honest answer is that the effect is real, the magnitude is contested, and the individual variation is larger than either. Those three things can all be true at once, and most arguments here are two people holding different parts of that.
Happy to go further on any of that.
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Shop Reference StandardsOne thing that is still open after A1cHero_PHX’s answer:
How people are distinguishing a supplier having a bad batch from a supplier on the way out?
OP back with an update, since a thread like this is useless without one.
Went back through my own correspondence with an earlier supplier and the warning signs were all there in the replies, weeks before the quality changed. I was reading the product and not the behaviour.