On: DIY mechanical keyboard switch lets you set its ac...

[caboteria]

In the opposite direction: I had a keyboard once that I set aside for a couple of years and when I tried to use it again some of the keys didn't register reliably. It took a couple of days of use before everything worked smoothly.

[lsaferite → caboteria]

Sounds like contact corrosion (assuming it was a mechanical keyboard)