The date a maker stops updating a product, after which new security holes stay open.
Like a product recall that never gets a repair: the maker stops fixing it, and the flaws stay.
Patch Management flags devices on an operating system past end of support, because there is nothing left to patch. A vCIO roadmap plans replacements.
Can I keep using an unsupported computer? Keeping it off the network or fully isolated lowers the risk. A plan to replace it is the real answer.
Every WILDCARD card exists to solve one named problem. Find yours.