Confidentiality VS Authentication - real-life example

canadio

"The block cipher modes ECB, CBC, OFB, CFB, CTR, and XTS provide confidentiality, but they do not protect against accidental modification or malicious tampering" (Source: Wikipedia)

Can anyone give a real-life example of this?

e.g. If I have an AES-XTS encrypted disk, how can this be tampered with?