View Quarantine

I can’t quite figure out how the quarantine works; after reading the instructions, I understand that it is specific to the antivirus, but I don’t grasp exactly what gets moved there.

The headers contain x-axigenvirus-level values ​​ranging from 1 to 5. If the x-axigenvirus-level is above 2—say, in the event of a false positive—the file is often deleted; what should I do if that file is actually needed?