Re: Bewildered. (That's grown-up speak for "wtf")
Regarding to the "Why do we need that", the question can be answered by googling the actual device. Unless the model number has a typo, this particular device is an industrial grade washer for restaurants or similar places. One selling point is the capacity of over 200 glasses, not exactly a con- or prosumer grade appliance.
I can see a few reasons why a large gastronomy outfit might want a dishwasher that "calls the boss" when it is done or needs attention. There may be more than one of those, the "bing" that signals a finished cycle might be drowned out by ambient kitchen noise etc.