Bastiaan en Lily's blog

I'm sure one could write a book on ATM interfaces and how bad they are. I'm not going to do that though the realization as an IT person is that I rather have people who haven't got an inkling of proper interfaces but are geniusses on safeguarding electronic money transfers writing the ATM software then the other way around :)

I'm just going to rant a few lines on a very simple thing that not only applies to ATMs but to many other scenarios as well..

Now there will be ATMs out there that do this diffferently but most I've run accross have the same sequence.
1) You insert your card, it asks if you want to know you bank balance or want to get some money out,
2) after you make a money selection it will ask you for your PIN,
3) it then asks you if you want to print a receipt,
4) hopefully you get some money.

Pretty basic simple stuff really. The problem I'm ranting about today is option #3. The nice thing about ATM interfaces being so similar is that you know what to expect. When you come to option #3 there are two schools of people:
A) those that don't trust banks and press yes so they have a receipt just in case something goes wrong
B) those that think its a waste of paper and press no.

I think its safe to say that both groups of people are so used to the interface they automatically press their prefered answer without ever reading the message.

However, today as any number of days in the past, out local ATM machine was out of paper and the message at #3 changes to:
3) This ATM currently can not print your receipt. Do you wish to continue?

Lets look at our two groups or people's response:
Group A automatically presses  YES as they always do. They get their money and then get very furious with the bank the ATM is not printing their receipt and send of irritating letters to the bank to complain
Group B automatically pressed NO as they always do and they have to start over again. The second time around they take a little more time to read the message and because they didn't care about the receipt that can't be printed in the first place, they end up pressing YES.

So whats the simple solution? Change the question so the answer would make sense to the person if the ATM wasn't out of paper. Lets change the message to:
3) This ATM currently can not print your receipt. Do you wish to cancel?

Let's look at our two groups of people again:
Group A automatically presses YES and now are hit by the scenario they have to do everything again. Initially upset they end up at the screen again, read the message properly and realize the system just saved them from aggrevation. If they really want the receipt they cancel again and walk away. If they make the consious choice not to have the receipt they press NO and get their money anyways.
Group B automatically presses NO, get their money and walk away without ever realizing the message was different.

A very simple change in the interface makes both groups of users alot happier. This is also the message to any other person designing an interface, always make sure in a question scenario YES/NO answers are consistent to the user. Users are really bad at actually reading the message. The anwers they are most likely to pick should either be the safest or the answer most likely to be the correct one. If available that answer should also always be the default selected answer.