"When you design UI, it has to be intuitive. If a user does something wrong, the first reaction of rookie developers is, “Stupid Users!”.
While some users may not be exceptionally bright, if they make mistakes using your software, most likely it’s your fault. I ran into a couple of such issues within the last three days.
1. While placing an order in one online store, I’ve entered my credit card number and pressed the button Submit. After a round-trip to the server (this was a thin client Web application), I got an error page stating that the credit card number is invalid. Actually, the error message was very friendly and warm. It suggested, “Consider removing spaces from the credit card field”. I was so grateful! Indeed, I’ve entered my CC number as groups of four digits separated by spaces. Removed the spaces, another round trip to the server, and it took it!
Now I’m talking to you, the moron programmer who implemented this form. Have you heard that coders are allowed to perform string operations? Some advanced programmers even know how to programatically remove spaces from a string of characters. Guess what, it take less time than to program an error message stating that this stupid user should remove the spaces.
2. I spent two days in Atlanta attending Devnexus conference for Java developers. On the way back, I was checking in at the Delta’s kiosk. To identify myself, I’ve inserted my credit card into a special slot. The checking process was fast. I arrived earlier, and Delta’s software suggested that there is another flight to Newark, NJ an hour earlier and for mere $50 I can get a seat on that plane. Being a cheap bastard, I politely rejected this option. I can spend this hour having a dinner in a restaurant with my laptop and Boingo Internet, which I’m subscribed to.
So I picked up my boarding pass and started to look for a cozy place that has martini and an electric outlet in the wall. All of a sudden, this thought came to my tired mind, “Taking an earlier flight costs an extra fifty bucks, but on the other hand it’ll save me money on dinner at the airport. Eureka!" (Continued via Net Developer's Journal, Yakov Fain) [Usability Resources]