Learn in the textbookFundamentals of Information Security and the Information Assets to Protect
DefinitionLoss (紛失) is damage in which information, or the media or equipment that hold it, go missing, so it cannot be used when needed.
ExplanationThe property that information can be used when needed is called availability, and loss is the state in which it has been harmed. It happens when a laptop or USB memory stick carried around is left behind, or when no one can find where documents were stored.
AnalogyYou drop your wallet, and the money inside is no longer yours to spend.
Memory hookThe kanji 紛 means to get mixed in with other things. Read the word as something that got mixed in and lost from sight.