An example from real life of how ergonomics still can improve. Below are two boat tickets for the same cabin on the ferry from Harwich to Hoek van Holland. The one on the left is for an adult, the one on the right is for an infant. At first glance they look similar, but they are different and only the one for the adult can be used to open the cabin door. They both fit in the slot inside the cabin for turning on electricity.
Here is what went wrong, because as you might have guessed these are my tickets… My wife and other son were in the cabin next to me and my son. I went over to my wife’s cabin for our nightcap which we usually have. I had to keep on the night light for my son and put the wrong ticket in the slot! No way back in and my son did not dare to come from his bed when he heard me shouting. I will not go into the details, but the proceedings involved me on bare feet at the guest service, a new ticket for the wrong cabin, me just not kicking in the door, me on bare feet at the guest service again, an escort to the room by a serviceman and a brief but clear explanation to the serviceman why I thought this was upsetting.
Now to prevent these unsettling events from happening to other people, my suggestion is to issue tickets with the same functionality in all cases. It is useless and even more unergonomic to issue tickes that cannot open the door to the cabin, even if it concerns an infant.
And for anyone that claims I should have paid better attention I would like to finish with a quote from Donal A. Norman’s The Design of Everyday Things. “While we all blame ourselves, the real culprit – faulty design – goes undetected.”