Switches for the buttons go bad, the rollers can corrode making for not so smooth movement and the rollers need cleaned. Opticals either work fine or they don't work at all (some early MS mice tended to die and had a recall). -----Original Message----- From: Noel Chiappa via cctalk Sent: Wednesday, January 24, 2018 2:24 PM To: cctalk at classiccmp.org Cc: jnc at mercury.lcs.mit.edu Subject: Re: Keyboard "enthusiasts" Huh? I've got old ball mice I've been using for years; they don't wear out. The wires do get flaky after a long period of use (at which point I stop using them - easier to switch than to chop an inch off the wire - the issue is where it goes into the mouse), and you do have to clean them regularly, but other than that... Noel --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus