This guy figured out why Logitech's mouse buttons are failing so quickly, and it's because they ironically used more expensive, "ruggedized" buttons rated for 50 million clicks, but neglected the operating voltage
Basically, Logitech heard y'all say the MX518 was the best mouse ever.
They copied part numbers from that mouse for all their new products, like the Omron D2F switches rated for 20 million clicks - your MX518 still works, after all, right?
They actually got newer, more expensive versions of those switches rated for even more clicks - 50 million clicks.
These switches are designed to run at 5 volts and 10-100mA. The MX518 did, but most mice in the past 5-10 years haven't run at that high a voltage or current. Most run at 3.3v and ~1mA, especially battery powered mice.
3.3v and 1mA is off the charts for the rated spec for these Omron switches. If the voltage and current are too low, like in modern Logitech mice, the super thin oxide layer that forms on the metal contacts inside the switch after a few months/years makes the switch bounce. The switches are not mechanically failing, they are just not designed to run at these specs.
Ironically, their switches would have lasted longer if they had picked a cheaper switch rated for only 5 million clicks, because the material in these less rugged versions has a wider "wetting current" range and can actually operate at their tiny current.
TLDR: They didn't try to cheap us out, but they did make a stupid electronics engineering mistake in the name of marketing.
It may sound hard to believe that a company as smart and reputable as Logitech would do something as crazy as buy parts that aren't rated for their operating current and voltage, but you can look up these parts spec sheets yourself, and you can see what voltage and current your mouse switches are operating at yourself. It's crazy but it's true.