Last night, in an epsiode of Subway, by which I mean I was in a Subway shop, having yet another placebo-healthy-sandwich, I had an epiphany. It was an obvious one, but it was so obvious that it had clearly eluded all concerned.
The door of the subway shop opens inwards. The only thing you can grab to pull it is a yale-style lock. This lock is not a latch, but in fact a dead bolt. You turn the lever through 180 degrees and the blot slides across. You turn it back and it unlocks. Simple. When unlocked, the lever can be used as a mini handle and the door just pops open. Of course people look at a yale and try to turn it, which would lock the door, so there's a neat 2" square sign above the yale which reads "To open door, just pull" or some such. I should have taken a photo.
Edit: I took photos
Anyway, I first found the door a tiny bit confusing, for like 3 seconds, then I learned to pull it. I can use a door. When I arrived at the shop last night, though, the door was pushed to, but the yale bolt was across, stopping the door from closing properly. "Oh, someone didn't know what they were doing with the door", I thought, "Perhaps they should learn, or read the sign". I regret thinking that.
I bought my sandwich, sat down, and a child came into the shop, bought a drink, went to the door to leave and started playing with the yale lock. I watched him, amused, as he locked us all in, unlocked us in, eventually looked at the sign, pulled, eventually got the door open, and then looked back, apologetically, as though it was not his fault, and left, feeling embarrassed.
Then it hit me.
It wasn't his fault. In fact, it's not anyone's fault that they don't know how to use that door. The door is to blame. I'm not being sarcastic. This door is to blame. There's a good reason we KNOW the door is to blame. It's the little laminated sign above the lock, the one means of opening the door (and also the means of rendering it unopenable and locked).
Now, I've harped on about the "Patronising Laminated Sign" before, but this 2" square of laminated paper is not a patronising sign. It's something else. This is the "Absolving Laminated Sign". The sign has been put in as a disclaimer. It really says "The responsibility for being unable to open the door is yours now". Why should a door, one of the simplest forms of machinery, require a sign to explain how to use it? There's no good reason that a door wouldn't be bloody obvious.
There is a reason in this case. The yale lock. The only means of opening the door is a small box with a lever on it. The lever "affords" turning. You turn the lever and the door is locked. In fact, the obvious thing to do with a lever is turn it, in the hope that it will release the door. The lock in this case is not the sort which disengages when you turn the lever in the unlocking direction - it has a roller-style end, which means it can be pulled open, even when slightly engaged in the frame. So turning the lever when the door is unlocked won't unlock it any more. It is totally non-obvious to grab a lever and just pull it.
The door needs a big fixed handle. The big fixed handle is what people instinctively would grab for and, since it only affords one action, pull towards them. All the people stumbling at the door can be fixed by taking off the sign and adding a handle. Whoever, fitted the door probably thought a handle was unnecessary, since the door will open from the inside by pulling anything that's fixed, like the yale lock. This "optimisation" has removed the need for a handle, but added a confusing means of using a door - i.e. pulling something that says "twist me".
So, I told the staff member who was serving. He understood, but I don't think he saw it as the revolution. He mentioned the suggestion box. I didn't see him joining my campaign. So I wrote a suggestion card out. I posted it in the box. Then I said to the other member of staff that I bet he'd seen loads of people struggling with the door. I explained about design, affordances and why the door's design is broken. It's really obvious anyway that you put a handle on a door, but somehow it eluded the person who wrote the sign. Writing a sign is not a solution. I told him that I would pay for the handle if it didn't prove to solve the problem.
Somehow I doubt a handle will appear.
If it does, then I will claim it as a victory.