I remember a few months ago when I came to work, there was a paper on our Wittenborg FB 7100 coffee machine saying:
It’s broken. Please don’t keep pressing the buttons!
That day me and my team mates didn’t drink coffee till I saw a colleague with a cup of coffee in the meeting room. I asked him where did he get the coffee when the coffee machine is broken? He replied that the machine is working and he has no idea who put the note on it.
Long story short it turns out that a guy who was new to the company tried to take coffee from the machine but saw “Out of service” on the display and no matter what keys he pressed the device was not responding. So he kindly put a note there to save some time for others. But the old-timers who take coffee every morning knew what’s the issue and took their coffee anyway. You know how? All you have to do is to wait a few minutes till the machine boils the water.
Another colleague who didn’t know the trick said:
To me “out of service” means that it is indefinitely broken and out of service. I would wait for the them to fix it rather than stupidly punching the buttons.
And I do agree. “Out of service” doesn’t have the properties of a good error message: it doesn’t clearly identify the reason for the error and it doesn’t offer any solution.
It’s a super-duper coffee machine and without it no work will have been done in the office (no, we don’t get paid for converting coffee to urine! ;) ) so it’s important that it works well. It’s the core machine that keeps the office running… some sort of power plant.
It’s a feedback issue. It’s not really hard to fix this. Instead of “out of service” it can say “Boiling water. Please wait.” and show a progress bar. This machine shows a progress bar when pouring coffee so it is capable of doing so. The size of its water container is known to the device and it can exactly calculate how long it takes to boil the water so the solution:
- shows the reason for the error (boiling water)
- indicates an action to solve the error (waiting)
- shows an indicator (so that user can decides for waiting)