BethLabQueen said:The pattern that distinguishes a bad batch from an exit is behaviour rather than product.
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.
NurseAsh_DET 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.
InsuranceTom said:I disagree that testing history is decisive.
Coming at InsuranceTom’s question from a different direction. Most of what circulates confidently in this community traces back to one summary of one study, and the qualifier was dropped somewhere in the third retelling.
Ask again with the specifics and you will get a better answer than this one.
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Shop Reference StandardsA narrower follow-up, since the general answer is now clear:
What a vetting checklist should actually contain, as opposed to a list of things that are easy to fake?
Reporting back.
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.