Sometimes investigative journalism can bring down a president, as in the case of the Watergate scandal. Other times it will do something even more important, like explain why the McFlurry machines at McDonald’s always seem to be out of service.

After taking notice of the many McFlurry fans on Twitter complaining that the equipment always appears to be inoperable, The Wall Street Journal conducted an inquiry into the soft-serve scandal. While McDonald’s was reticent to provide a complete answer, the problem appears to be one related to sanitation. Company policy dictates that each machine undergo a thorough four-hour cleaning process to kill bacteria, which involves partial disassembly and can put the machine out of commission during off-peak hours on a daily basis.

To further complicate the delicious issue, it’s believed that the machines are also prone to failure. According to the Journal’s Julie Jargon, a 2000 survey by a franchise consultant found that 25 of 100 restaurants polled said the ice cream units weren’t working properly.

All of it conspires to put a dent in both McDonald's dessert profits—estimated at $255 million annually—and your late-night cheat meal. Franchisees in France and Spain don't seem to have the same issue, however; the two territories recently unveiled a McFlurry Party that consists of an oversized tub of ice cream and additional cups for sharing. America does not currently appear to have the McFlurry bandwidth for such ambition.

[h/t Thrillist]

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