Most components are rated for use at a specific temperature range, and for storage in a certain range too. Parts made to handle greater range for the military (MIL SPEC) have wider temperature range, and so are used in places where extreme temperatures are expected, like aerospace and things like that. They are able to handle lower temperatures both in use and during storage. But my point is that aren't these temperature ranges exceeded with cryogenic treatment? Don't certain materials become brittle? And like you said about the electrolyte in capacitors, doesn't that cause problems too? Are there some things that cannot be treated?