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Mark Graban

Six Sigma

Simple, Brilliant, Error Proofing at the Amazing In-N-Out Burger

A little help for the not-so-common sensible

Published: Monday, April 11, 2011 - 05:30

I was in Los Angeles on Tuesday, and I had a little extra time on my way to the Burbank airport, which meant a rare treat—lunch at the famed In-N-Out Burger. I don’t mean to be that guy who tweets what he eats, but my lunch is pictured at right.

The main picture I wanted to share is a simple example of perfect mistake-proofing (aka error proofing or “poka-yoke”). There is a possible customer error that could be made in many fast-food or deli restaurants: throwing the reusable tray into the trash bin.

Ineffective organizations post signs, warning, and exhortations. Smart organizations error-proof.

Here is the error proofing—the hole that you throw your wrapper, cup, and food waste into is round and smaller than the rectangular reuseable tray.

I didn’t really fight or shove the tray while staging this photo, but it was clear that the tray would not fit into the round hole. Problem prevented: It is physically impossible to trash the tray. (Yes, I know you’re not supposed to throw away the tray. I think this is obvious to most customers.)

In comparison, most Quiznos restaurants merely admonish the customers with signs saying, “Please Do Not Throw Away Baskets.”

The Quiznos tray fits into the trash hole (which is huge). I wonder how many trays they lose.

Does Quiznos really believe that its customers think the hard plastic trays are disposable? If you do accidentally drop the tray into the dirty trash and food scraps, are you likely to want to retrieve it? I suppose I could have titled this story, “Quiznos Thinks You Are Dumb,” but of course that isn't true, they are just shifting the mistake proofing onto the customer rather than deal with it themselves.

If Quiznos had followed In-N-Out's lead of mistake proofing the trash, they could have filled that high-visibility space with a “Thank You for Your Business” message.


About The Author

Mark Graban’s picture

Mark Graban

Mark Graban is an author, educator, and speaker in lean health care, through his company Constancy Inc. He is a faculty member for the Lean Enterprise Institute (LEI) and vice president of improvement and innovation services at KaiNexus, a technology company that helps organizations spread continuous improvement. He is founder of the Lean Blog and is author of Lean Hospitals: Improving Quality, Patient Safety, and Employee Engagement, Second Edition (Productivity Press, 2011) and, with Joseph E. Swartz, Healthcare Kaizen: Engaging Front-Line Staff in Sustainable Continuous Improvements (Productivity Press, 2012), both recipients of the Shingo Professional Publication and Research Award.


Service at in-n-out

I love this place.  They have a terrific product, process, and they treat their people well.  I live in Washington State - not blessed with this chain yet.  However, I've visited In-N-Out's in AZ, NV, and CA - each time the place is busy, and unbelievably clean.  Even the bathroom.  IMO, 5-Guys - while a descent burger - doesn't touch In-N-Out.

Brian Hughes
Vice President
Apollo Associated Services, LLC

In-N-Out Burger

5 guys uses NO trays--I wonder if which is greener:  disposing of the bag with food oils or washing trays.  It would be interesting to see the trays someone tries to trash at In-N-Out--my experience has been, when you make something "idiot-proof, the idiots simply mutate...

Can't rather than don't

This is an example of Henry Ford's safety principle "Can't rather than don't."


Instead of reminding people, "Don't throw the tray away," the design means they can't throw it away.

Still a bad tray design

The hole that the garbage goes into is very small compared to the tray. I would expect many messy fingers trying to push the waste through the hole. Why not scrap the rectangular tray for a round one designed on the same principle as a manhole cover. That would make for a waste hole at the garbage almost the same size as the tray making the tray very easy to empty and the tray design would make it impossible to push it through the hole. Need to think "out side the box'.

The hole isn't that small...

I should have taken two pictures. It's not tough to throw away your trash. It wasn't messy. 

No ! Good Tray Design .... PLUS!

I disagree, AHORYZA.  It's a good tray design -- a manageable size that can be dumped one-handed, and deep so as to minimize the liklihood of items falling off in tranist.  PLUS, In 'n' Out doesn't put any kind of paper "place mat" onto the tray the way McDonald's and other chains do.  Those paper mats serve no purpose other than advertising -- they don't beautify the presentation of the food in any way, nor do they provide any kind of sanitation assurance.  In 'n' Out limits its "on-tray" advertising to a couple of brief messages on the burger wrappers and the beverage cups.  And when dumping the contents of the tray at McDonald's, more often than not that paper mat adheres to the plastic tray, increasing the amount of time I have to spend cleaning and emptying it, and frequently requiring a 2nd hand in order to free the mat from the tray.

Try 5 Guys

5 Guys Burgers 'n Fries goes one better - all orders, whether take out or eat in, are put in a brown paper bag.

No trays to worry about.

Leaner - but not as environmentally friendly since paper greasy with food oils is not good for recycling.

Choose your evil.


Why a bag?

Automatically giving everyone a bag doesn't seem like the greenest thing to do, either.