and
"A correct alert was sent to the retailer, but was subsequently subject to human error in the way it was handled in store,"
So was the guy a shoplifter or not? Because apparently not and the human error was acting on the alert it seems. Sounds like the front fell off.
Facial recognition software doesn't actually "recognize" your face, it selects a series of points the algorithm thinks important in a pattern and matches them to other patterns in the database. It's the same technology, though less advanced, than fingerprint readers. Until better filters for the patterns were developed there were a lot of false positives in the fingerprint readers as well, and I suspect this will be the case with facial recognition software as well.
Faces are way less unique than fingerprints unless you are using a camera with such high resolution that you can see the individual hairs, pimples, birthmarks, moles, freckles, and other tiny details, and even then, only if you are analyzing it at that level of detail after using fixed points to unwrap the image into a flat UV map for comparison.
Statistically, no two people have the same fingerprint, so it's just a matter of comparing enough points to achieve the desired confidence level. At a shape/structural level, lots of pairs of unrelated people have faces that are too much alike to reliably detect the difference, likely because there's not as much genetic diversity as one might assume.
Compounding this is the fact that a fingerprint is detected by being pressed flat against something, whereas face shape has to be recognized from arbitrary angles.
Any approach that does not stitch together multiple camera angles to get a complete image of the entire face and then unwrap it into a high-res UV map and then use the result as a secondary filter pass after structural comparison is doomed to fail frequently when presented with an adequately large number of people. There are simply too many people that look far too much alike even within a fairly small geographical area like a state or small country, much less the entire world.
Accuracy is the wrong number to give. Accuracy is right answers over wrong answers, without any info about whether they were false positives or false negatives. What you really want is a relationship between the number of false positives and by total positives, or perhaps the relationship between false positives and total negatives. The latter is called specificity (true_negatives/ (true_negatives + false_positives)), and gives you an indication of how likely people are to be falsely accused. This needs to be incredibly low.
But the better number would be false_positives / (false_positives + true_positives), because that would tell you how likely it is that someone flagged is really the person in question.
Either way, for this purpose, the only rational way to use the tech is to watch flagged people more carefully. Trying to escort them out of the store is going to be a disaster of false positives, for all the reasons previously mentioned (look-alikes, limitations caused by camera perspective, etc.).