For our app, we looked at creating a guideline on what to display when data is (temporarily) not available. The scenario: it's a technical application, a service engineer clicks a piece of equipment and the UI shows details about it in a side bar (name/value pairs). Some fields might be not available for technical reasons, say a communication layer/bus is not working, the software is not providing it yet, etc. We looked at several options, like not showing a value at all (i.e. an empty value), showing a '-', a '?', 'N/A', 'n/a' etc. Examples:
|Physical Address||Serial Number||Status|
We wanted to settle on 'N/A', as an empty value, ? or - do not communicate intent (see also here).
Still, we identified that for most people there is a distinction between:
- Not Applicable - Value is not relevant for this piece of equipment (and will never be)
- Not Available - Value is relevant, but just not available right this time
and N/A can be translated as both (one could argue how important this distinction is for the user of course). We also got this feedback when presenting it. Any other ideas or guidelines on this?