I have no idea how they obtained their figures but, from my own use, I have not had their bad experiences. I have been using MSE since its first release for Beta testing. By default, it downloadsa new definitions on first boot or on a daily schedule. This is exactly what it has done for me. I suspect the testers have their Windows update schedule wrongly configured.
Here is my own most recent record. The white out is my own making to hide personal data. The gap in updates is due to a recent period of holiday, from which I have just returned.
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