This seems like an interesting and useful process design concept on one hand, and on the other hand, it also sounds like a Japanese buzzword for foolproofing (in fact, the article notes that the term was originally “baka-yoke”, which is literally “foolproof” or “idiot-proof”). On the one hand, I don’t think Toyota invented the concept of foolproofing; on the other hand, giving it a cool buzzword gives you an excuse to talk about it, which means you’re more likely to actually do it when appropriate.
I’m also kind of amused at how the entire business world basically said, “man, this company made super reliable cars in the 80’s and 90’s[1], let’s learn their secrets” and it turns out that once you strip away the exotic Japanese veneer, it’s mostly just systemized common sense. Which is not a minor thing to do, to be fair, except it’s easy for businesses to take good, well-systemized ideas and utterly misapply them.
[1] As far as I know, they still make reliable cars. But you can still drive a 92 Camry today if you wanted to with little fuss. By definition, we’re 26 years away from seeing if today’s Camry is quite that reliable.
The way in which the term is used in the manufacturing industry is a different from "foolproofing" in practice. Generally, a Poka-Yoke is a step added to a process that requires an operator to stop and think about what is going on and whether everything is within spec before proceeding with the next step.
One example I can think of would be a torque tool used in a critical step of the assembly process. Since modern factories allow different models of roughly similar product types to be assembled on the same production line, it is important that the torque tool is run using the correct settings for each model. In this example, the operator has to scan a barcode on the vehicle and the corresponding barcode on the computerized torque tool before the tool will work. This not only sets the tool to the correct setting, it forces the operator to stop and think for a second when the tool doesn't work. By doing this as the first step, it also ingrains the knowledge of which model number the operator is working on as they consciously have to scan the right barcode on the tool as there's a unique barcode for each variant they'll see coming down the line. That way they are more likely to catch any incorrect/mismatched parts tied to later stages of assembly carried out at their station (i.e. they know they are working on Model X Sport but the parts bin shadowing this chassis has a cosmetic piece that is only for the Model X Limited).
Also, I;ve always found it funny that the phrase sounds like poke-a-yoke (yoke, as in yokel) given how it's used in the industry to describe a way of prodding someone to pay attention.
It's hard not to be dismissive of what appears to be a simple set of concepts, but you're missing on an opportunity to learn a very cool set of skills here. I recommend that anyone who wants to live a better life and do better work read books on the Toyota Production System and Taiichi Ohno. As for Poka-Yoke, It's a word that seems simple but when used in industry contexts communicates a deeper set of requirements than just "make it foolproof". Also, don't undersell how useful systematizing common sense is (and how difficult its application can get).
"Common sense" isn't common. Not only that, it's ridiculously unpopular to try to change people's ideas of what common sense is. You can see this even on HN when people suggest that programming language tooling should constrain defects.
It's interesting how much of "Japanese" manufacturing practice is really the work of W Edwards Deming, the prophet without honor in his home country.
This is not a buzz word, this is the name of the tool we use. 4/4 companies Ive been at used Poke-Yoke, Poka-Yoke, or Error Proofing interchangeably.
And while I dont own a Japanese car, I can verify the 'common sense' ideas had a resurgence as Toyota applied a process to these principles. It seems nearly every company MUST apply them or they are uncompetitive.
From a plant with 50 employees to a fortune 500 plant, I have not seen these 'misapplied'. Only excellence.
I find outsiders are pessimistic and are unaware that these plants are using SPC and have process engineers looking to optimize daily.
I used to work for a Toyota supplier years ago, and got to visit one of their ports where cars and parts enter the US from Japan for further assembly (like a mix of car garage and factory). It was striking how organized and neat everything is.
It all boiled down to "Kaizen", another simple concept meaning "continuous improvement." From what I remember, one implementation of kaizen was that employees were expected to stop what they were doing two or three times a day and spend 10 minutes organizing their workspace. This seeming waste of 20-30 minutes a day actually increased efficiency by having all tools in the right places at all times.
Working with them was a real eye-opening experience - it showed me how simple concepts can have a huge impact on a business when applying them consistently and with (sometimes maddening) discipline.
As I was reading this Wikipedia entry, I came upon the part where it said it was developed by Toyota and actually uttered out loud "of course it's Toyota!" I have nothing but respect for their work ethic and discipline.
They called it the obvious word in their own language, it's only a cool buzzword to non-native speakers reading English Wikipedia.
> systemized common sense
Of course. And still businesses are full of systemic problems, where common sense fails. Just like well written programs are just "systemized instructions", but most programs are buggy and brittle. Clarity in defining and executing on simple concepts is worth a lot.
It is surprising how many problems can be solved with common sense. Whta Toyota did was codifying it in a rather elegant way. They gained a considerable advantage by doing so.
Also surprising how hard the implementation of common sense can be. Also true that only a few companies really manage to implement lean / TPS methods correctly in the way Toyota did.
I don't really understand the point of your message, it feels like forced cynicism around the cultural reception of the term.
Perhaps you're saying that the phrase is akin to "big data" or "AI" in that it doesn't really say much. The idea that this concept can be misapplied doesn't serve well to steelman its useful core concept and philosophy which is timeless. My favorite example are electrical plugs [1]. Whatever beef you have with Toyota, Japanese, or buzzwords just seems inappropriate here and lowers the quality of discussion.
> As far as I know, they still make reliable cars. But you can still drive a 92 Camry today if you wanted to with little fuss. By definition, we’re 26 years away from seeing if today’s Camry is quite that reliable.
That has little to do with preventing manufacturing defects and more to do with preventing design defects. A defect-free car can still break down prematurely because it doesn't wear well, used incorrect materials, ect.
>I’m also kind of amused at how the entire business world basically said, “man, this company made super reliable cars in the 80’s and 90’s[1], let’s learn their secrets” and it turns out that once you strip away the exotic Japanese veneer, it’s mostly just systemized common sense. Which is not a minor thing to do, to be fair, except it’s easy for businesses to take good, well-systemized ideas and utterly misapply them.
This was basically all done over UAW's dead body. It's not like process engineers working at the big three in the 80s didn't want to do those things. They were aware of what industry best practices were as any competent professionals would be. They just couldn't get those best practices implemented until the Japanese manufacturers created an existential threat to the status quo.
Cyber security is in a similar situation today. The will to do the known right things is not there and won't be until there's an existential threat to the companies that are being lazy. Whether that threat will be regulatory, market based or something else but I guarantee little will change until it becomes a binary choice between change and going out of business.
> As far as I know, they still make reliable cars.
There's a pretty substantial lag between reality and market perception. All the people paying lightly used 3/4 ton truck and fullsize SUV prices for Tacomas and 4Runners with 100k+ on them had better hope that what they're buying today lives up to the reputation of vehicles sold 10-20yr ago.
>we’re 26 years away from seeing if today’s Camry is quite that reliable.
Unless they make a complete turd it will be more reliable because they hold their value well giving them a longer period of time when they are out of reach of customers who are hard on equipment.
Vehicles move down the economic ladder as they change hands. Rich people have more free cash flow to spend maintaining their car (especially preventative maintenance). This skews age based reliability data in favor of whatever vehicles wealthier people drive.
Economic factors make differences in vehicle reliability from brand to brand look much greater than they are.
If you want to see this in action look for 80s GM sedans on Craigslist in a state that salts the roads. The Buicks, Olds, and Caddys are over-represented because their first and second owners were more likely park them in a garage (or at least off the street), pay for preventative maintenance, etc. allowing them to stick around longer because they were (on average) in better condition than the equivalent average Chevy of the same age, had more useful life left, etc. The upscale cars had to get to their 2nd and 3rd owners before they were treated the way the Chevys were treated by their first and second owners giving them the appearance of greater reliability despite being the exact same platforms. the chevy might have 3-5 owners before going to the junkyard whereas the Caddy may have 4-7 (and therefore stick around for more years) because it basically starts off several rungs higher on the economic ladder.
One of my favorite examples of poka-yoke is the Apple MagSafe charger. The magnetic part itself is foolproof, sure. But the genius part is the small metal knob that meshes with the removable AC prong piece. It is impossible to insert that piece in any other way than it was intended, and the solution is unobtrusive, clean, and simple.
I still don’t get why they removed it. MagSafe was a great thing. Sure some people got things stuck in the connector but that is a much smaller problem than having your laptop pulled along with the cable when someone trips on your charger.
The metal knob actually is PE pin for the AC plug, which is used in some parts of the world with presumably stricter low voltage safety standards which would not allow for the chassis of macbook to float at what is essentially half of the mains voltage (this is why you get slight tingling sensation if you run back of your hand over macbook that is plugged into charger with two-prong plug).
One of my professors (I am an Industrial engineer) used the example of a SIM card. I imagine people can still get it wrong when putting it in, but much less so (ehem USB) because of that slight cut in the rectangle. It also helps a lot when manufacturing those things to get the orientation right.
Another mistake proofing anecdote I've heard was about one of his students interning at a company that packages soap. Somehow there were empty boxes going through the conveyors after some process change. Some of the mechanical engineers were already thinking about some modification to the conveyors that detect weight, etc. The IE student apparently simply went in one of the back offices and got a spare electric fan and pointed it at the conveyor so the empty boxes fly out. Troubleshooting doesn't have to be expensive.
That’s a story which I have seen a few variants of before this; I doubt this is really one of the professor’s students, it’s more likely an urban legend.
In my experience these things are developed over time in response to failure. Always keeping the poka-yoke concept in the back of your mind helps when designing systems, but you don't really know how people will misuse tools until they're in action.
From my understanding, poka-yoke addresses the problem where "[...] the mistakes are allowed to reach the customer".
In software, we know that the later a bug is caught, the more expensive (in terms of time / resources) it is to fix. So we want to catch bugs / mistakes earlier.
The "simple" idea that Poka-yoke introduces is to make it harder to make the mistake in the first place.
If a physical component can be mounted more than one way, but there is only one correct way, then design it such that it is impossible to mount it incorrectly. This can be done by making the mounting holes for the part asymmetrical, for example.
IMO, in software a similar concept would be to fail early and fail hard.
I guess that aligns with type systems in programming languages. The type systems make sure that the plain simple mistake of passing an integer in the place of a string is prevented. Of course more powerful type systems like Haskell fool proof it more if the developer is putting the effort of writing more types to restrict things more.
I think that's a clear implementation of poka-yoke on the programming languages level allowing developers to fool proof their APIs
This only works if you have a thermostatic mixer or consistent temperature of your hot water.
The gold standard is a pressure-balanced thermostatic mixer, which always outputs the same temperature at the same setting. Most of them come with two knobs, "temperature" and "flow". I miss the one I had a while ago.
It's a book about how minor design differences can basically change your life. It will make your life miserable, because you will start noticing all the stupidly bad design decision and blame the designer in most cases.
The term is used quite often in manufacturing.
For a part when picking, for example, a part may have two colored squares on the label so the operator looks at the color on the squares to validate as an extra step. We call the colored squares the poka-yoke.
This concept is very useful, not only in manufacturing but also at home. As somebody else has explained, MegSafe used this principle. Another great example is our dryer at home: the filter that needs to be cleaned every month or so has to be plugged back in in a certain way. They perforated they filter such that there’s absolutely no way to plug in back in the wrong way. Another great application would be gas vs diesel knobs at gas stations. I’m not sure whether new cars/pump provide that already
I'd never heard of this, but it's an excellent concept that I try to apply to my daily living.
For example I accident-proof myself against spills by keeping a beverage in a place where it's unlikely to be knocked over, but if it is that the consequences are easy to deal with rather than soaking a keyboard or something. In physical terms it mostly boils down to minimizing the potential energy of everyday objects.
[+] [-] philwelch|7 years ago|reply
I’m also kind of amused at how the entire business world basically said, “man, this company made super reliable cars in the 80’s and 90’s[1], let’s learn their secrets” and it turns out that once you strip away the exotic Japanese veneer, it’s mostly just systemized common sense. Which is not a minor thing to do, to be fair, except it’s easy for businesses to take good, well-systemized ideas and utterly misapply them.
[1] As far as I know, they still make reliable cars. But you can still drive a 92 Camry today if you wanted to with little fuss. By definition, we’re 26 years away from seeing if today’s Camry is quite that reliable.
[+] [-] cc439|7 years ago|reply
One example I can think of would be a torque tool used in a critical step of the assembly process. Since modern factories allow different models of roughly similar product types to be assembled on the same production line, it is important that the torque tool is run using the correct settings for each model. In this example, the operator has to scan a barcode on the vehicle and the corresponding barcode on the computerized torque tool before the tool will work. This not only sets the tool to the correct setting, it forces the operator to stop and think for a second when the tool doesn't work. By doing this as the first step, it also ingrains the knowledge of which model number the operator is working on as they consciously have to scan the right barcode on the tool as there's a unique barcode for each variant they'll see coming down the line. That way they are more likely to catch any incorrect/mismatched parts tied to later stages of assembly carried out at their station (i.e. they know they are working on Model X Sport but the parts bin shadowing this chassis has a cosmetic piece that is only for the Model X Limited).
Also, I;ve always found it funny that the phrase sounds like poke-a-yoke (yoke, as in yokel) given how it's used in the industry to describe a way of prodding someone to pay attention.
[+] [-] dammitcoetzee|7 years ago|reply
[+] [-] pjc50|7 years ago|reply
It's interesting how much of "Japanese" manufacturing practice is really the work of W Edwards Deming, the prophet without honor in his home country.
[+] [-] MrEfficiency|7 years ago|reply
This is not a buzz word, this is the name of the tool we use. 4/4 companies Ive been at used Poke-Yoke, Poka-Yoke, or Error Proofing interchangeably.
And while I dont own a Japanese car, I can verify the 'common sense' ideas had a resurgence as Toyota applied a process to these principles. It seems nearly every company MUST apply them or they are uncompetitive.
From a plant with 50 employees to a fortune 500 plant, I have not seen these 'misapplied'. Only excellence.
I find outsiders are pessimistic and are unaware that these plants are using SPC and have process engineers looking to optimize daily.
[+] [-] mirkules|7 years ago|reply
It all boiled down to "Kaizen", another simple concept meaning "continuous improvement." From what I remember, one implementation of kaizen was that employees were expected to stop what they were doing two or three times a day and spend 10 minutes organizing their workspace. This seeming waste of 20-30 minutes a day actually increased efficiency by having all tools in the right places at all times.
Working with them was a real eye-opening experience - it showed me how simple concepts can have a huge impact on a business when applying them consistently and with (sometimes maddening) discipline.
As I was reading this Wikipedia entry, I came upon the part where it said it was developed by Toyota and actually uttered out loud "of course it's Toyota!" I have nothing but respect for their work ethic and discipline.
[+] [-] sooheon|7 years ago|reply
They called it the obvious word in their own language, it's only a cool buzzword to non-native speakers reading English Wikipedia.
> systemized common sense
Of course. And still businesses are full of systemic problems, where common sense fails. Just like well written programs are just "systemized instructions", but most programs are buggy and brittle. Clarity in defining and executing on simple concepts is worth a lot.
[+] [-] hef19898|7 years ago|reply
Also surprising how hard the implementation of common sense can be. Also true that only a few companies really manage to implement lean / TPS methods correctly in the way Toyota did.
[+] [-] news_hacker|7 years ago|reply
Perhaps you're saying that the phrase is akin to "big data" or "AI" in that it doesn't really say much. The idea that this concept can be misapplied doesn't serve well to steelman its useful core concept and philosophy which is timeless. My favorite example are electrical plugs [1]. Whatever beef you have with Toyota, Japanese, or buzzwords just seems inappropriate here and lowers the quality of discussion.
[1] https://image.slidesharecdn.com/pokayoke-150112043214-conver...
[+] [-] corpMaverick|7 years ago|reply
[+] [-] unknown|7 years ago|reply
[deleted]
[+] [-] gwbas1c|7 years ago|reply
That has little to do with preventing manufacturing defects and more to do with preventing design defects. A defect-free car can still break down prematurely because it doesn't wear well, used incorrect materials, ect.
[+] [-] dsfyu404ed|7 years ago|reply
This was basically all done over UAW's dead body. It's not like process engineers working at the big three in the 80s didn't want to do those things. They were aware of what industry best practices were as any competent professionals would be. They just couldn't get those best practices implemented until the Japanese manufacturers created an existential threat to the status quo.
Cyber security is in a similar situation today. The will to do the known right things is not there and won't be until there's an existential threat to the companies that are being lazy. Whether that threat will be regulatory, market based or something else but I guarantee little will change until it becomes a binary choice between change and going out of business.
> As far as I know, they still make reliable cars.
There's a pretty substantial lag between reality and market perception. All the people paying lightly used 3/4 ton truck and fullsize SUV prices for Tacomas and 4Runners with 100k+ on them had better hope that what they're buying today lives up to the reputation of vehicles sold 10-20yr ago.
>we’re 26 years away from seeing if today’s Camry is quite that reliable.
Unless they make a complete turd it will be more reliable because they hold their value well giving them a longer period of time when they are out of reach of customers who are hard on equipment.
Vehicles move down the economic ladder as they change hands. Rich people have more free cash flow to spend maintaining their car (especially preventative maintenance). This skews age based reliability data in favor of whatever vehicles wealthier people drive.
Economic factors make differences in vehicle reliability from brand to brand look much greater than they are.
If you want to see this in action look for 80s GM sedans on Craigslist in a state that salts the roads. The Buicks, Olds, and Caddys are over-represented because their first and second owners were more likely park them in a garage (or at least off the street), pay for preventative maintenance, etc. allowing them to stick around longer because they were (on average) in better condition than the equivalent average Chevy of the same age, had more useful life left, etc. The upscale cars had to get to their 2nd and 3rd owners before they were treated the way the Chevys were treated by their first and second owners giving them the appearance of greater reliability despite being the exact same platforms. the chevy might have 3-5 owners before going to the junkyard whereas the Caddy may have 4-7 (and therefore stick around for more years) because it basically starts off several rungs higher on the economic ladder.
[+] [-] war1025|7 years ago|reply
[+] [-] jihadjihad|7 years ago|reply
[+] [-] codetrotter|7 years ago|reply
[+] [-] dfox|7 years ago|reply
[+] [-] mglhn|7 years ago|reply
One of my professors (I am an Industrial engineer) used the example of a SIM card. I imagine people can still get it wrong when putting it in, but much less so (ehem USB) because of that slight cut in the rectangle. It also helps a lot when manufacturing those things to get the orientation right.
Another mistake proofing anecdote I've heard was about one of his students interning at a company that packages soap. Somehow there were empty boxes going through the conveyors after some process change. Some of the mechanical engineers were already thinking about some modification to the conveyors that detect weight, etc. The IE student apparently simply went in one of the back offices and got a spare electric fan and pointed it at the conveyor so the empty boxes fly out. Troubleshooting doesn't have to be expensive.
[+] [-] teddyh|7 years ago|reply
[+] [-] camtarn|7 years ago|reply
https://en.wikipedia.org/wiki/Pointing_and_calling
[+] [-] toomanybeersies|7 years ago|reply
[+] [-] synodinos|7 years ago|reply
Visual rhyme, Accessibility, Affordances, Mistake-proofing (“Poka-yoke”), and Defensive design.
https://medium.com/@dio/5-things-to-consider-when-evaluating...
[+] [-] 2dollars27cents|7 years ago|reply
In my experience these things are developed over time in response to failure. Always keeping the poka-yoke concept in the back of your mind helps when designing systems, but you don't really know how people will misuse tools until they're in action.
[+] [-] gorb314|7 years ago|reply
In software, we know that the later a bug is caught, the more expensive (in terms of time / resources) it is to fix. So we want to catch bugs / mistakes earlier.
The "simple" idea that Poka-yoke introduces is to make it harder to make the mistake in the first place. If a physical component can be mounted more than one way, but there is only one correct way, then design it such that it is impossible to mount it incorrectly. This can be done by making the mounting holes for the part asymmetrical, for example.
IMO, in software a similar concept would be to fail early and fail hard.
[+] [-] sharno|7 years ago|reply
I think that's a clear implementation of poka-yoke on the programming languages level allowing developers to fool proof their APIs
[+] [-] MrEfficiency|7 years ago|reply
Now I put my handle in the correct location and its warm everyday.
[+] [-] jaggederest|7 years ago|reply
The gold standard is a pressure-balanced thermostatic mixer, which always outputs the same temperature at the same setting. Most of them come with two knobs, "temperature" and "flow". I miss the one I had a while ago.
[+] [-] gattilorenz|7 years ago|reply
Read this, if you haven't: https://en.wikipedia.org/wiki/The_Design_of_Everyday_Things
It's a book about how minor design differences can basically change your life. It will make your life miserable, because you will start noticing all the stupidly bad design decision and blame the designer in most cases.
[+] [-] ninjakeyboard|7 years ago|reply
[+] [-] tsuresh|7 years ago|reply
[+] [-] baxtr|7 years ago|reply
[+] [-] User23|7 years ago|reply
For example I accident-proof myself against spills by keeping a beverage in a place where it's unlikely to be knocked over, but if it is that the consequences are easy to deal with rather than soaking a keyboard or something. In physical terms it mostly boils down to minimizing the potential energy of everyday objects.
[+] [-] fouc|7 years ago|reply
[+] [-] csense|7 years ago|reply
[+] [-] manceraio|7 years ago|reply
[+] [-] avodonosov|7 years ago|reply