I can vouch for that. For me it's the scroll wheel.

I've been through a Logitech G703 and a Corsair Sabre Pro and both failed the same way. I've also seen it happen to a Razer Deathadder Essential. The shitty mechanical encoder goes janky after a few months and basically makes scrolling unusable, as scrolling the mouse wheel either doesn't get detected or is interpreted as going the opposite direction. Yeah they can be 'fixed' by either blasting air into it which sometimes works for a bit or worst case, soldering on a replacement encoder, but even that's just a temporary fix as it's only a matter of time before that fails too. I can't deal with unreliability like that.

Older mice more commonly used to use optical encoders which tend to last much longer but finding a new mouse with an optical encoder isn't as easy. I finally broke down and got a Zowie the other day which should hold up a bit better in theory and only time will tell. I feel silly spending so much on a mouse, but I just want one that works.