For a long time, the term "NFT" has seriously misled retail investors. The word "token" makes people mistakenly believe that NFTs are purely on-chain, when in reality, the images are stored on off-chain servers. To be more accurate, "non-fungible token (NFT)" should be changed to "non-fungible offchain mapping to onchain token" or "NFOT" for short. Currently, NFT images can be backed up on multiple servers when projects have funds. But even multiple servers aren't guaranteed to be completely secure, and things could get worse if they run out of money. In short, just remember that NFTs are stored on servers. If the server goes down, they're gone.