You might remember last month when I wrote about my human error in putting an upside down coffee mug under my Keurig brewer. Oops.
Mike Thelen, a good friend of mine and this blog, sent me a little gift that's intended to prevent future mixups:
This really cracked me up… as you can see, green arrow up = good. Red arrow up = bad.
As was pointed out by a Twitter follower, when I shared this there, the color coding wouldn't work for those who are color blind, which I'm not. The mug also has the Lean Blog logo to help tell if the mug's right side up or not. As far as I know, my mug is a one of a kind. Thanks, Mike!
I have NOT that same mistake since… problem solved?
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For this to be truly error-proofed, the cup could only be inserted one way – the proper way.
Perhaps a mug with a unique flange fits into a tongue-and-groove joint fixture, and the void in the Keurig for setting the cup will only fit one size of mug. Also an interlock device sits in the tray that must be pressed down by the center of the mug before the Keurig will operate (if the mug is inserted upside down the Keurig will not function).
Of course, those implementations cost a little money. I do like the idea of painting big red “NO! NO! NO!” on the bottom of the mug so you are quickly alerted to the placement defect…
Yeah, the color coding is a pretty weak form of error proofing as it doesn’t truly PREVENT the error… just hopefully makes it more apparent.
Here is an example of coffee machine error proofing that was somewhat confusing and probably over-engineered:
https://www.leanblog.org/2010/02/a-coffee-machine-thats-mistake-proofed/
I made another incremental improvement to the mug… ah, Kaizen. Every day, a little better. It’s still not perfectly mistake proofed, of course.
I haven’t made the “upside down mug under the Keurig” error again, with or without that mug. How long will “being careful” work?