When it comes to errors, error prevention – through great UX and well-built code – is first and foremost. There’s a lot more to say about error prevention (this blogger has some wise thoughts, and I blogged about it a while ago), but this post is about when errors do happen.
This could be because:
- The user makes an error – for example, typing the wrong password
- There is a bug or issue with the software or service – for example, the famous Twitter fail whale when the service was overloaded
The Google material design guidelines has some useful insight into error types.
Nielsen’s well-established error message guidelines suggest error messages should:
- be explicit
- be human-readable
- be polite
- be precise
- offer constructive advice on how to proceed
To paraphrase, an error message should tell a user clearly what the f**k is going on and what to do about it.
For example, take the following display, snapped on my phone in Manchester Airport’s departure lounge before Christmas, an hour or so before our flight was cancelled (poor us).
The message, in the centre of a blank display which should have shown flight departure times:
- is useless to its intended audience (ordinary human beings), as it is filled with techno-babble
- is literally unreadable in places
- provides no guidance on how to fix the error and restore the system
- may have been marginally clearer if its button read ‘Terminate program’
- includes a close icon, whose purpose is unclear (does it close the message or terminate the program?)
No error message in the context of a departure lounge display board is a good error message – all passengers want to do is see departure times, and can do nothing to fix the error. It’s a prime example of where error prevention is far more important.
Nevertheless, error messages like this persist in other contexts – we’ve probably all seen them many times. There’s no excuse – error messages should simply be simply and clear.
And I would add something to the Nielsen list: ‘design for the worst’. Sure, ‘hilarious’ 404 messages – when the user hits a page that no longer exists – can be fun. But not everyone is in the mood to be entertained. Even the friendly mailing service Mailchimp acknowledges in its tone of voice guidance that:
“It’s always more important to be clear than entertaining. When you’re writing, consider the reader’s state of mind. Are they relieved to be finished with a campaign? Are they confused and seeking our help on Twitter? Are they curious about a post on our blog? Once you have an idea of their emotional state, you can adjust your tone accordingly.”
So does Mailchimp’s current 404 error message breach its own rules? You decide…
Green swamp-monster not withstanding, Mailchimp’s error message is readable, concise and offers a clear next step (the navigation or search box) – unlike the message in the airport.