BenResearch_OR 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.
DadBodDave said:Eight months with one supplier, then a change in how they communicate that I noticed before I noticed anything about the product.
Vendor reputation tracking for vendor vetting: I maintain a personal spreadsheet with every order I've placed — date, vendor, batch number, Janoshik result, personal efficacy assessment (1-5 scale), and any issues.
After 19 orders across 4 vendors: average purity 98.3%, zero sterility concerns, 2 shipping issues (all resolved). This data gives me confidence in my current source and documentation if issues arise.
I encourage everyone to track their orders systematically. Community data aggregation makes us all safer.
MikeFit_NJ said:I disagree that testing history is decisive.
Adding the part of the answer the thread has not reached. There is a difference between no evidence and evidence of no effect, and this subject is one where the two get swapped freely in both directions.
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Shop Reference StandardsOne thing that is still open after tyler_CSCS’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.