There are a ton of people suggesting it's related to ESD (electrostatic discharge), which is IMO the most likely culprit. The effects of ESD are pretty wild and generally invisible to the naked eye. We have yearly ESD safety meetings at my job and are required to wear ESD-safe shoes/jackets and use anti-static wrist straps when working with any hardware (which I rarely do, but I still love the "perk" of getting free ESD Birkenstocks every couple years).