|17||17||It is important that the test targets "regular user tasks", i.e. the intention of the user must be part of the expected workflow, just actioned the wrong way, and also that the user's mistake has an actual (not ''potential'') consequence on the data integrity or workflow. That means, if the user puts in values in wrong syntax, and the system is able to still save the right values in the record, then that is ''not'' an inconsistency but tolerant behavior. If though the user puts in values in wrong syntax and the system saves a wrong value, then that's a bug. And of course, no user action should ever lead to a HTTP 500 "Internal Server Error" (whereas other error messages may be a proper response to the user's mistake).