Poka Yoke

Another great Firefox example is the shortcut for "close all the tabs" (ctrl+shift+q), which also happens to be adjacent to "go to previous tab" (ctrl+shift+tab). Depending on your preferences, there won't even be a warning popup if you accidentally press it.

Tip: you can use ctrl+shift+n to reopen the lost window.

I accidentally clicked "Forget about this site" on an item with google domain in Firefox history recently. Cue 5-minute freeze and having to re-login, not to mention losing the entire browser-local googling history.

My personal favourite is the "clear" button at the bottom of forms, right next to the "submit" button.

"as is YouTube jumping to a different part of the video every time you bump one of the numerical keys on your keyboard. "

Niche workflows? This is one of the most useful features! :)

I'm an industrial engineer, so this is all right up my alley!

My favorite example is a two-part foam injection machine. They needed to change the injection head, and accidentally put it on backwards. The parts mixed and worked their way back in the supply lines, solidifying along the way. Hundreds of thousands of dollars in lost productivity, multiple weeks to get it fixed. They promptly switched the coupling so it was impossible to put the injection head on backwards.

So, uh, is this poka-yoke that you poke in the yoke? Nice.

That's more of a learned behavior that helps you consciously check everything; it's almost the opposite of pokayoke. Implementing pokayoke would involve locking out (or making it incredibly hard) for rail workers to continue a process without confirming that everything has been done as intended.

Maybe. I think it wouldn't qualify for a few reasons. I'm sure others would be able to justify this as being a form of error proofing.

1. From Toyota Production System An Integrated Approach to Just-In-Time by Yasuhiro Monden, "A mistake-proofing system consists of a detecting instrument, a restricting tool, and a signaling device. The detecting instrument senses abnormalities or deviations in the workpiece or the process, the restricting tool stops the line, and the signaling device sounds a buzzer or lights a lamp to attract the worker's attention." I don't think pointing and calling works for this since there is a human in the loop that would have to detect, for example, the speed is too fast for the segment of track, restrict the speed by slowing the train down, and call attention to another operator to help. The goal is to eliminate the human from this process to ideally free them up to do work that respects their humanity [1].

2. Pointing and calling is only 85% effective as called out on the Wikipedia page for it. The benefit of mistake proofing is 100% built-in quality control according to the Wikipedia page.

3. From practical experience in automotive part manufacturing, our customers did not accept human based interventions or process changes as a form of error proofing. The error proofing needs to be built into the process and it can't be something that an operator can by pass. Pointing and signalling can be bypassed if the employee chooses not to do it. I'm sure there is ways of bypassing some error proofing systems, but that's what the customer wants.

Error proofing is part of a system called autonomation []. One of the goals is to be able to have multi-skilled workers be able to work within a cell. Basically the human operator takes on a loading and unloading focus in the manufacturing process. Several operations would be performed in sequence. The operator would put the raw material in at one side of a machine cell, transfer it to the subsequent operations until the last operation has been completed. The goal is for the piece to be produced with minimal waiting time between each successive operation and for the machines to be able to detect if a defect has been produced.

[1] https://michelbaudin.com/2014/04/12/more-on-toyotas-respect-...

[2] https://en.wikipedia.org/wiki/Autonomation

When writing and running SQL one-offs interactively, I will surround it with `if 1<>1 begin end` or comments, or add syntax errors at the top so that I won't accidentally run it without first selecting the part I want to run. I should get into the habit of writing `begin; rollback` instead for extra-safety.

And I always write the WHERE clause before the DELETE or UPDATE keywords.

The above solution unfortunately doesn't work for those of us who use fzf (or other fuzzy runners), since that RUN_SCARY_THINGY=yes var will be part of the matched line which you will run inadvertently in your coffee-deprived mind. I rarely make mistakes while consciously typing out commands, but running commands with wrong arguments because I didn't pay enough attention on the matched line does happen semi-regularly. Doesn't help that since doing stuff with fzf is much faster than typing out full commands, that your brain sometimes just doesn't have enough time to ask -- wait, should I be running this right now?

That seems a bit unfair since it literally comes from the direct translation of 'idiot proof'.

It's true that you can benefit from idiot-proof design without being an idiot, but I would argue that you could market a microwave that doesn't turn off when you open the door, plastered with warnings and maybe a mandatory course on how to operate it. An idiot-proof version would have safeguards that everyone could benefit from, but then saying that it's a fundamentally different concept just seems needlessly combative.

Fun fact: the microwave door switch does not only switch the thing off, it also shorts the power line. If the switch contact were melted and fused together unable to disconnect, it pops the breaker.

Arguably a (valve-based) pumping system without valves wouldn't be considered error-prone but rather non-functional? (I might be missing something, though, since I don't really know whether heart valves are dual-purpose like that.)

You mean the metal knob on the mains side of the power brick? I don't see how the backward insertion of anything would be an issue there.

AFAIK the metal knob is the earth connection (which is not used on EU plug, which is very annoying).

Sure, some Linux distros (or is it MacOS?) ask for confirmation before executing `rm -rf /`, which breaks the typical UX of the command but prevents bad mistakes.

Pretty much all good software design practices exist to prevent mistakes by constraining behavior.

It would be interesting to try and formalize it and make it more specifically analogous to what's in manufacturing.

It can apply anywhere. For software, there are packages for servers that replace the standard shutdown/reboot commands with something that prompts for confirmation first, or in the case of e. g. GitHub, you must type out the full name of the repo you're trying to delete to ensure that you're not deleting the wrong one.

Maybe something like throwing an exception when updating a collection that is being enumerated over.

Or perhaps the constructor pattern requiring object construction to complete before a reference to the object is available.

Common on industrial stamping presses also. Operator loads metal sheet, then needs to activate the press with two physical buttons, separated with enough distance that it can only be done with two hands.

Probably because it's a slogany sort of invented term.

Katakana sometimes is used to draw attention to words that would be normally written in hiragana or kanji. It can sort of function like italics or bold type that way.

In this case it might be used to signify that it is a specific method rather than just a collection of words. The english equivalent might be capitalizing the letters in Six Sigma to refer to a specific industrial quality process rather than the math term.

Probably because ポケ is, causing katakana contagion of the 除け part.

(I made up "katakana contagion"; don't bother searching.)

For safety, yes. This prevents the car from lurching forward (or backward) if you start it thinking the transmission is in park/neutral, when it is actually in gear.

Most modern cars have a lockout, preventing you from starting the engine unless the brake (or clutch) is pressed. However, some older cars do not have this feature.

Yes. Always. If your transmission is defective somehow you don't want the car to lurch when you start it.

If it’s a push button ignition you have to, so almost all new vehicles. On keyed automatics, no. There are VERY few cars on the road that would start in drive or reverse or low. This is an old warning.

Manuals on the other hand, again, almost all have a clutch interlock to start, but a lot of trucks and jeeps can have clutch defeats and will move when the starter is hit while parked in gear. It’s pretty dumb, but there are tiny scenarios off road you might want that. Most people just don’t want to press the clutch to start for some reason. In many of these vehicles it’s as simple as pulling a fuse.