The Dangers of Failing to Mistake Proof your Process
I recently rewatched this episode of The Office and Creed’s failure to properly mistake proof his process causes problems throughout Dunder-Mifflin. Poor, Debbie Brown!
“I’m supposed to spend 4 hours a week doing a quality check at the paper mill and of course the ONE YEAR I blow it off, this happens.”
-Creed
Hopefully this serves as a much needed wake up call. Customers are disgusted! Dunder-Mifflin will most likely want to consider a way to prevent obscene watermarks from reaching their customers in the future.
Luckily, there are ways for the company to rectify this.
Mistake proofing is a proactive approach to detecting or preventing defects by designing and implementing creative devices and procedures. You might know it by the the Japanese term Poka Yoke, which translates in English to “avoids mistakes.”
Mistake Proofing is the first step in involving front-line workers in problem solving activities. Many of the best mistake proofing ideas come from the people who do the work.
There are two major types of Mistake Proofing Devices:
I. Detection
Makes abnormal conditions immediately recognizable.
The detection method’s objective is to design a quality assurance process that makes it easy for workers to spot abnormal conditions and stop them in their tracks—before they are passed downstream.
In Lean organizations, once a detect is detected, it’s beneficial if workers possess stop the line authority. This involves the capability and expectation for them to pull an andon cord, a device that shuts down the machine and signals the need for supervisor support to help resolve the issue.
Once the issue is resolved, the operator is free to re-start the production line. Andon triggers immediate action, preventing the defect from continuing its path downstream.
Workers have 3 responsibilities regarding detection:
Check that the incoming work is free of defects.
Verify that there are no defects.
Never knowingly pass defects downstream.
It doesn't seem like this occurred at the paper mill. The impact was magnified since the quality assurance manager blew off his duties.
While Creed failed to do his job, this does not account for why the mill’s workers also failed to catch the defective watermarks.
It’s not clear from the clip, but if it it walks like batch production and talks like batch production, it might just be batch production. Continuous flow is the way to go. But that’s for another post.
II. Prevention
Removes the opportunity for error, making a defect’s occurrence impossible.
Prevention takes mistake proofing a step further. Benjamin Franklin is credited with the aphorism, “an ounce of prevention is worth a pound of cure.” This captures the essence of the prevention method.