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I don't think it's a pattern by the manufacturer. I think it is an abnormal failure, that I have not heard reported much at all. (Which is evidence that it is abnormal rather than designed.)
Being 2 years old, the mouse is out of warranty. Aside from cleaning the terminals of both the battery compartment and the batteries themselves, with a clean dry cloth possibly moistened with a little rubbing alcohol, and trying one more time to let the batteries last... I think your mouse might need replacing, if only to save money on batteries.
What do you think? These cordless mouse devices have a tendency to save power by turning partially Off at times. Does your mouse seem to have lost that tendency?