Amsterdam parking ticket vending machine. Click photo's to enlarge.

poor labeling
The interface of this Amsterdam-based parking meter offers an excellent example of poor labeling (providing the user with information about what a button or control does). Instead of the buttons being labeled with words like 'set time', 'pay' or anything else that makes sense, the manufacturer decided to color-code them and then explain in the fine print beside the actual interface how the interface works.

how to operate it
To start you have to push the red button.  By inserting the amount of money you determine what parking ticket you'll get, and finally you use the green button to confirm. The yellow button at the top is used to select electronic payment (bank card), in which case you use the two small black buttons at the button to determine the amount. If you did something wrong, there is no 'correction key'. You just have to wait 20 seconds or take out your bank card. I've used it a couple of times now, and it still confuses me and I need to read the instructions again. Pretty bad for a 'walk up and use' product.

why?
I may be speculating here, but often poor labeling is a consequence of internationalization. Tailoring the language used on a product to the country it will be used in is expensive. So can manufacturers resort either to symbols, to label everything in English or to making the labels ease to replace, which they are in the case of the parking meter. Just replace the written instruction, and you've replaced the labeling. But with some consequences for the use of the product.

another example of poor labeling
See also my earlier confrontation with the TU Delft office telephone, where the labeling is done via a replaceable piece of paper. The person that came up with the new labels used 'dial tone' to indicate which button to use when putting a call through, which is rather confusing.

More uselog posts on ticket vending machines:
> Users fix ticket machine interface themselves
> Please do not hump the vending machine
> Good design: Dutch railways ticket vending machine
> Ticket machine update: the cost of learning something new
> Possibilities of RFID daze designer of card-charge machine