I'm looking for a term which I'm pretty convinced exists but I have forgotten. Roughly, it describes the fact that a system or tool has several modes of operation / states and behaves differently in either of them. For instance, a document editor can be in read-only and normal states.
I remember having been advised in HCI and ergonomics courses to avoid designing systems or tools that will behave differently depending on the mode or state they're in. It may be that I don't remember so well and that the advice was specifically about behaving unexpectedly because of "statefulness". For instance, my document editor's Print function should behave the same in read-only and normal modes. Does anyone have examples of good or bad applications of "statefulness" that provided good UX or caused usability issues?
If I wanted to give myself a general design guideline with regard to "statefulness", I would want to prevent the states in which a system can be from causing interaction breakdowns by influencing how the user should interact with the system, without the user being aware of the state. Hence, general guidelines that can be applied to decide if a specific incarnation of "statefulness" is likely to be nefarious to users are also welcome!