[VVV] Machines don't lie???? Geeze. Where ever did you get that idea?
Yes they do my friend, they most certainly do. Merely running the same Beckman Elise based testing platform most certainly does not automatically = 100% the same results.
There would be no need whatsoever for NATA if that were the case.
Fact is that there are any number of variables that can & do influence outcomes...ranging from the QC material used to the individual operator skills & everything in between.