Talk:Five whys

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Comments[edit]

This never actually described what '5 Whys' is, just gave its domain, history, and criticism. As someone looking for an answer to 'What is "5 Whys"?' I am left with no good answer, just more links to QA domain articles. I presume that it is about asking the question "Why?" or "Why is (something)..." but this is never explained, nor is the rational using this unknown thing explained. Inclusion of these things would help people like me understand the article and the subject.


In answer to the question, and hoping that the questioning person still keeps up with these things, is simply this: the "5 whys" technique is a method of finding to "true" or "root" cause to an issue or problem. In incident investigations, typically seen in logistics management (trucking, warehousing and labor industries), this technique is often taught for determining exactly how and why an incident or injury occurred. / The goal is to prevent recurrence of costly incidents or injuries. Therefore, in busy warehouses where product is frequently damaged (resulting in increased costs for replacement of such product) or employees report constant muscle strains (causing increased Workers' Compensation insurance rates), the "five whys" might be taught as a simple way for lower management or supervisors to find the root cause, address the true key issues, and create effective corrective actions that minimize recurrence rates. Simply punishing/ treating a single individual does not deal with the underlying cause if the problem actually develops during training or from lack of enforcement. / There are, of course, other methods of questioning personnel about such matters, such as the "fishbone diagram". The five whys method, however, is fairly simple and easy to remember. / In order to be truly effective, however, these methods have to be used repetitively. An investigator has to ask questions several times, and in different ways, to note any discrepancy or inconsistency. In doing so, he may create the feel of an "interrogation," and thereby encounter resistance from intimidated or offended personnel. To overcome this, investigators may choose to have other team members review and question the incident with the individual, and then compare notes in search of inconsistencies again. Poekoelan (talk) 16:55, 17 October 2013 (UTC)[reply]


I removed the following addition to the example because while it is mildly humorous, it also expresses opinions that generally cannot be substantiated or have no bearing on the problem. Also, every concern listed in this proposed addition is beyond the control of the person performing the analysis; such issues are not usually considered "root causes" per the most widely accepted definitions of "root cause".

  • Why? The recommended service schedule is usually not reliable and auto shops are not trustworthy; as well, I do not have the time or money to spend on costly maintenance with the off-chance that I am charged a price that's not considered highway robbery (sixth why, true root cause)

- 72.141.21.242 13:28, 11 May 2007 (UTC)[reply]


Not all problems have a single root cause. If one wishes to uncover multiple root causes, the method must be repeated asking a different sequence of questions each time.

Reordering the sequence of questions just gives Why Why Why Why Why. You can try this in any order you like. 67.183.140.180 (talk) 06:49, 22 September 2015 (UTC)[reply]

A generalisation of the 5 Whys[edit]

A related, but much more profound method, than the one discribed in this article would the decision tree - with more than 2 alternatives at each node.

--Werfur (talk) 19:10, 26 May 2014 (UTC)[reply]

Bad example[edit]

The example of a 5-whys analysis of a car not starting illustrates an almost perfect example of the 5-whys failing. First you need to ask the right questions - and in this case there are almost five whys for every 1 of the first five whys. The car won't run. Why1: well it could be compression, ignition, fuel, air, mixture, timing, or the starter isn't operating as designed - i.e. the engine isn't turning over. Let's assume that the starter isn't operating as designed. Why2: well, it isn't getting sufficient energy to the windings. Why3: the solenoid isn't reaching the end of it's travel. Why 4: let's say the battery is dead. Why5 because we have been cranking the engine for 20 minutes. So we charge the battery. It still won't turn over. Is this a new set of whys? It certainly is not - because our original problem was that the car won't start and it still won't and we still don't know why. So Why6: the most likely cause is a bad connection - this connection could be at the battery, at the starter, in a relay, a fuse or any point in the wiring harness. I can tell you that the most likely points are at the battery terminals themselves or the cable ends exposed to acid or salt, or the ground between the starter and the engine block. So do we clean each of these up individually? Or do we hit them all at once? Well we hit them all at once. We don't ask why. The car still won't start. We could insert about a dozen whys in here without getting any closer to the answer. Why7: we have a bad starter. So we replace the starter. The engine finally turns over, but it still won't start. Why8: We don't have ignition. Why 9: Because we have a bad ground to the ignition coil. We fix this, but the engine just sputters and dies. We investigate and find that the compression is off. Why 10 because the timing belt has jumped a tooth. Why 11: because the belt tensioner isn't functioning. We replace it and reset the valve timing. It still won't run Why 12: because the ignition timing is off. Why 13: because the distributor is wet Why14: because its raining and we have had the hood up by the side of the road for 4 hours. We dry it off. It still won't run. Why 15: because the plugs are fouled. Why 16: because we have been trying to start a worn out engine for 6 hours in the rain without ignition. Why 17: because the car won't start.

To make it simpler and shorter, cause and effect are rarely obvious when it comes to starting a car. If your battery is dead and your alternator is gone it does NOT imply that the dead alternator caused the battery to fail. In most cases it is the other way around - a bad battery puts undue load on the alternator causing it to fail. Changing the alternator just burns up another alternator - and performing regular maintenance will not prevent your battery from failing in the first place. Asking "why" five times is not going to get you even close to a solution if there is more than one thing wrong with a vehicle - or a manufacturing process, or a computer network. It's a childish oversimplification of the diagnostic process latched onto by fools who happen to be in positions of authority without a clue as to how their organizations or the devices they use everyday actually function. This should be pointed out with some emphasis, I think.

Sorry for the rant. Suffice it to say, you need a better example. — Preceding unsigned comment added by SteveMCanada (talkcontribs) 09:17, 20 December 2013 (UTC)[reply]


Problem: The example is bad. 1. Why? It was intentionally oversimplified. 2. Why? The original author of the example didn't want to include much technical detail. 3. Why? He didn't want to confuse people with details specific to one example. 4. Why? He figured people wanted to learn more about 5 Whys, not about automotive troubleshooting. 5. Why? Because this is an article about 5 Whys on WikiPedia, not a frickin' auto repair manual. — Preceding unsigned comment added by 173.35.59.3 (talk) 06:20, 8 October 2014 (UTC)[reply]

Presuming the example is appropriately brief[edit]

One continued analysis is:

  • The vehicle will not start. (the problem)
  1. Why? - The battery is dead. (First why)
  2. Why? - The alternator is not functioning. (Second why)
  3. Why? - The alternator belt has broken. (Third why)
  4. Why? - The alternator belt was well beyond its useful service life and not replaced. (Fourth why)
  5. Why? - The vehicle was not maintained according to the service schedule. (Fifth why)
  6. Why? - Though scheduled, the maintenance did not get the responsible human's timely attention. (Sixth why)
  7. Why? - The service was only recommended in a passive schedule, not a schedule actively notifying the responsible human. (Seventh why)
  8. Why? - The vehicle maker relied on human memory to initiate maintenance actions ... and ... human memory is inherently lossy; humans forget pending actions at various rates. (Eighth why)
  9. Why? - The vehicle maker chose a passive maintenance schedule as cheaper/better option than any mechanism actively notifying the responsible human. (Ninth why)
  10. Why? - The vehicle maker discerned that the reduced effectiveness of a passive maintenance schedule is a more acceptable risk to potential sales and profitability than the increased cost of a time-based notification system. (Tenth why, one possible root cause)

An alternate analysis is:

  • The vehicle will not start. (the problem)
  1. Why? - The battery is dead. (First why)
  2. Why? - The alternator is not functioning. (Second why)
  3. Why? - The alternator belt has broken. (Third why)
  4. Why? - There was no sensor measuring belt stretch and impending breakage, or notifying the responsible human for preventative replacement. (Fourth why)
  5. Why? - A derated passive maintenance schedule was chosen as a cheaper/better option than the sensor and notification mechanism. (Fifth why)
  6. Why? - The vehicle maker discerned that the reduced effectiveness of a passive maintenance schedule is a more acceptable risk to potential sales and profitability than the increased cost of a sensor-based notification system. (Sixth why, another possible root cause)

--LoneStarNot (talk) 17:16, 4 February 2019 (UTC)[reply]

Or, framed in terms of processes (_____ing)...

  1. Why did starting the car fail? – The battery is dead; it it not storing sufficient charge. (First why)
  2. Why did storing charge fail? – The alternator is not transmitting charge to store. (Second why)
  3. Why did transmitting charge fail? – The alternator is turning. (Third why)
  4. Why did turning the alternator fail? – The belt meant to turn the alternator can no longer be used. (Fourth why)
  5. Why did using the belt fail? – The belt was used beyond its recommended replacement interval, and broke. (Fifth why)
  6. Why did replacing the belt fail? – The maintenance event was not submitted to the scheduler (user) for entry in the process queue. (Sixth why)
  7. Why did scheduling maintenance events fail? – Maintenance event scheduling is only passively linked to maintenance requirements (user polled); no time-based notifications(interrupts) were implemented. (Seventh why)
  8. Why did implementing time-driven maintenance notifications fail? – a) No flexible data displays were not part of the 1995 vehicle design. b) Timely user maintenance would reduce supplier revenue from emergency maintenance servicing. (Eighth why) LoneStarNot (talk) 00:59, 27 October 2020 (UTC)[reply]

Article name change - 5 Whys > Five Whys[edit]

The name of this article has been changed a couple times in the past week by Lmatt without discussion or evidence as to why it was needed. The name has been "5 Whys" which seems to be most common in the literature, and was switched to "Five whys" and then again to "Five Whys." I asked about this on that user's Talk page, but did not receive a response, so am bringing it here. What do people think about this? --- FULBERT (talk) 14:52, 4 September 2019 (UTC)[reply]

@FULBERT: I have to admit to not being familiar with this particular article, until it showed up for other reasons on my radar. MOS:NUMERAL dances around the issue, without talking about it in article titles. This section at WP:NCNUM talks about when the topic of an article is a number or contains a number (like Form 1040), but apparently not the case where it starts with one. This is part of the Wikipedia:Manual of Style (dates and numbers), and it seems to me it ought to have something to say about it. I'll maybe raise a talk page discussion there, linking this.
However, regarding your first question, I don't think due diligence has been done before the move, and this should have been discussed, first. The editor who carried out the move, has a history of doing things their way, and this is not their only move. As this has not been discussed, and there is a legitimate question of what MOS and WP:AT would recommend in this case, I think this should have been considered a potentially controversial move and should not have been carried out without discussion. Mathglot (talk) 23:50, 10 September 2019 (UTC)[reply]
See WT:NCNUM#Titles with a number first, words second. Mathglot (talk) 00:08, 11 September 2019 (UTC)[reply]
I agree with everything you stated here Mathglot, and thank you for taking an interest in this. I hope others may also share this passion so it can be determined after this non-discussed move. --- FULBERT (talk) 01:56, 11 September 2019 (UTC)[reply]
@FULBERT and Mathglot: The capitalization seems to be a problem. Per WP:NCCAPS and MOS:CAPS, titles should be in sentence case unless there is a special reason why another capitalization is required, such as being the title of a work (book, film, etc.). In this case I see no special reason to capitalize both words in the article title (or in each occurrence of the title within the article), so it should be five whys instead of Five Whys. Other article titles of similar procedures are in sentence case, such as: why–because analysis, root cause analysis, issue tree, issue map, mind map, eight disciplines problem solving, affinity diagram, value-stream mapping, failure mode and effects analysis, business process mapping, business process modeling, etc. I don't care whether "five" is a numeral or spelled out, because I have seen it written both ways in the literature (although per MOS:NUMERAL integers from zero to nine are spelled out in words in Wikipedia article text, and since the article title occurs many times in this article's text it would make sense to follow that rule in the article title as well), but in either case "whys" should not be capitalized in Wikipedia. Biogeographist (talk) 02:07, 11 September 2019 (UTC)[reply]
@Biogeographist: Thanks for your comments. Yes, I noticed the caps issue as well, but that seemed more straightforward; my uncertainty was more about the initial number-word. Mathglot (talk) 07:24, 11 September 2019 (UTC)[reply]

@FULBERT and Mathglot: It appears there is no objection to change of capitalization of the article name (to "Five whys")? — Preceding unsigned comment added by Biogeographist (talkcontribs) 17:23, 6 October 2019 (UTC)[reply]

I changed the name to "Five whys" as there appears to be no opposition. Biogeographist (talk) 18:38, 9 October 2019 (UTC)[reply]
Overall, happy with this resolution of this renaming. --- FULBERT (talk) 12:07, 10 October 2019 (UTC)[reply]