pete_manc_UK 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.
Dr.PeteFamMed 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.
PharmacoVig_BOS said:I disagree that testing history is decisive.
There is a second half to this that has not been said yet. The distinction that resolves most of these threads is between what is true on average and what is true for one person. Both are real; they answer different questions and get quoted as if they were the same one.
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Browse GL BiochemA narrower follow-up, since the general answer is now clear:
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.