The systems track all kinds of data and are decent at predicting failures before they get expensive.
So we schedule service, and then we throw away all the food anyway because the problem cannot be addressed remotely.
Suppose the condition is that temperature in the freezers is rising, producing active concern for the contents.
A smart person with the right access can see that, and also correlate it with other things.
Like:
The doors to the building are open, while the HVAC takes a break because the weather is temperate and isn't dehumidifying as it would be on a hot day?
And it's a holiday food-buying week, so the freezers' doors are open for buying and restocking more than usual?
If the refrigerant pressures and other stats also fit the scenario, then: The evap coils may just be iced up. If they can be defrosted from the comfort of your desk a thousand miles away, then that's pretty great. Just like what was done (to malicious extreme) here.
(You're a smart person. You could correlate these things yourself if this were your trade, save a trip [or many, many trips across a chain], and get paid to make these kinds of things happen remotely.)