Daily Archives: 29 - Aug - 2004

Real-life usability of warning signs.

We’ve probably all heard by now of the fact that most users will, when presented with a dialog that interrupts them from doing their work, will just get rid of the dialog as quickly as possible instead of reading it over. Bug 83495 is an example of this kind of bug.

Everytime I see this kind of bug report, I’m reminded of when I used to work at a video store on the local naval base. Being a naval base, we were prone to days with high winds blowing in from the sea, which would always wreak havoc with our doors (one Entrance, one Exit), as the wind would sometimes force the doors open. One particularly bad windy day, the wind actually broke the hinge on the door, which meant that the door was at risk of flying open and shattering the glass. The door that was broken that time was the Exit door.

That would obviously be sub-optimal if the glass were to be shattered. So what we did that day was lock the door shut. Of course this ended up confusing the customer who tried to leave through the locked door, so we put a sign on the door saying that it was locked.

This didn’t faze anyone, as people kept running into the locked door. So I printed up four full-page-size arrows, and taped them around the sign already on the door. This helped, but we still had people trying to walk through the door.

Being inventive, I took the opportunity to barricade the electronic scanner people walked through on the way to the exit, taping it off and putting signs up on the tape as well. This finally stopped everyone from trying to walk through the door.

Well, almost everyone. One of my co-workers walked in, and was walking around, and literally walked right into all the tape. It took us a few minutes to get the tape (and taped signs) off of her clothes.

Moral of the story: No matter how explicitly you warn about an action, you’ll still get people who activate the action unwittingly if they can. ;-)