> My personal favorite: "An unexpected error has occurred." (Apple!). Or the more casual phrasing "This should never happen." (open source!).
This is a pet peeve of mine. I've been known to write plenty of "This should never happen." error messages, but I pretty much always include a description of what assumption was violated. EX: "User token is null, this should never happen!" (in a part of the program that should be impossible to reach without a token). Even if it's useless to the end user, it's so much more informative to the programmer than a generic NPE and a stack trace, and most likely it at least provides a hint to the end user roughly what's broken.
This is a pet peeve of mine. I've been known to write plenty of "This should never happen." error messages, but I pretty much always include a description of what assumption was violated. EX: "User token is null, this should never happen!" (in a part of the program that should be impossible to reach without a token). Even if it's useless to the end user, it's so much more informative to the programmer than a generic NPE and a stack trace, and most likely it at least provides a hint to the end user roughly what's broken.