I have an example that was thankfully caught by internal QC before any other agency was aware. There was a situation in a diagnostic lab where a new processing technician (non-bench/wet lab position), responsible for accessioning specimen and distributing them to the proper department, was pouring off peripheral blood and bone marrow from original tubes into pour off tubes without indicating if the newly created pour off tube was PB or BM… this left it up to the tech in the wet lab to subjectively try and figure out if it was PB or BM (viscosity, presence of bone shards) which caused problems because testing specifically calling for PB or BM would be halted and turn around time would be delayed because the tech would be unsure by visual inspection and there would be no way to back trace the specimens origin. All patient information was copied over to the pour off tube but not the source type, PB or BM. Something small like missing a piece of information on a label, if caught by a governing agency would be severely detrimental to the company, write ups, fines, deficiencies, etc. This is why QC is so important in catching mistakes and maintaining quality.