Five Whys Definitin. As explained in the previus article, we define rt cause as simply the uncvering f hw the current prblem came int being. Fr a simple causal chain, it is the entire chain. Fr a cmplex system f interlcking paths and events, again it is the entire thing. Yu knw yu are dne gathering infrmatin when yu see the cmplete picture f hw this prblem came int being and are ready t cnsider what t d abut it. The fllwing are several tips fr making better use f the Five Whys prcedure. 1. Verify the cause befre prceeding. One way t imprve the use f the Five Why prcedure is t insist that all answers be verified (t the extent pssible.) It is ne thing t ask what caused smething and it is anther t knw the answer! It is nt enugh t give an answer that seems right r ppular. It is crucial that each link in the causal chain is the verified, true cause. False links will lead t ineffective crrective actins (at best) and disasters (at wrst). (Use the BPI Prblem Slving tl when cause analysis is required t verify a link.) 2. Find the cause first then decide what t d t fix the prblem. It is cmmn t cnfuse the cause f a prblem with the wrld s failure t implement yur slutin! Fr example, ne might see the cause f the increase in absenteeism as a lack f an absenteeism plicy. And, ne might believe the cause f a child eating ckies befre dinner t be the lack f discipline by the parents. Or, perhaps ne thinks the cause f a defective part delivered t a custmer was because we d nt have a final inspectin pint prir t shipping. Thugh a new plicy may affect absenteeism, a missing plicy des nt cause absenteeism. While discipline can affect a change in the child s behavir, the lack f discipline is nt the cause f the behavir. A child eats ckies
because she is hungry, and she thinks ckies are delicius. Installing an inspectin statin culd prevent the delivery f defective parts after they are created. But, installing an inspectin system will nt stp the creatin f defective parts. The existing series is: 1] create defective parts, 2] ship t custmer. The fcus nw shuld be n what triggered the prblem, tday, nt what t d abut it in the future. Learn the current sequence and use this knwledge t develp the best way t crrect the prblem. Ask, Hw did this prblem cme int being?, and lay ut the answer step by step. This is an histrical investigatin dn t change the system r anything else yet! Put a hld n ideas fr hw t prevent this prblem in the future. Lgically, deciding what t d t fix a prblem cmes after a full understanding f hw the prblem was created in the first place. 3. Use simple, nt cmpund cause statements. Prperly implemented, the Five Why prcedure will ften reveal higher level causes. Fr example: Parts failing at a high level Many wrkers using an imprper fitting technique Many wrkers dn t knw the prper technique Manager decided t cancel training Wrker staffing level reductins mandated But, ne prblem we have bserved with using the Five Why prcedure is that peple get stuck at ne level. When they shuld prceed deeper dwn the causal chain (frm prblem, t a part, t a prcedure, t the system, t a management decisin), instead peple get stuck prviding mre and mre detail abut ne link.
After cnsidering this, we nticed that peple get stuck because at sme pint they created ne (r mre) cmpund cause statement(s) in their Five Why series. Cmpund Cause Statements - Example: (Hw the mind interprets WHY? in parentheses.) Prblem: SUV Mdel Z exhaust system rattle (A) Why? (Why des the exhaust system rattle?) Because f a change f psitin f the bracket results in vibratin. (B) Why? (Why des the bracket psitin cause vibratin?) Because the bracket is t clse t the pipe resulting in vibratin. (C) Why? (Why des being very clse result in vibratin?) Because the vibratin frm the pipe and vibratin frm the rad are additive due t vibratinal harmnics. (D) Why? (Why are rad plus pipe vibratins harmnic?) STOP! (we are ff int a technical rabbit hle thinking abut HOW psitin created mre vibratins and nt prgressing deeper, back in time.) Asking Why? f a cmpund cause ften results in ur reversing the analysis t a cause-effect sequence (ging frward in time) and ut f the effect back t cause 5 Whys pattern. The reverse sequence f causes is interrupted because in cmpund sentences the mind becmes cnfused abut what Why? refers t. Statement (A) cntains a cmpund cause. Asking Why? tricks the mind int interpreting the questin as hw did bracket psitin result in vibratin? The chrnlgy is wrng. We re nt trying t explain hw the bracket psitin caused vibratin. We want t fcus n the bracket psitins and find ut What caused the bracket t be in that psitin?
Always wrk t g back in time frm cause t its cause nt frward explaining cause t its effect. Statement (B) als cntains a cmpund cause. The fllwing shws the Five Why prcedure withut the trap f cmpund cause statements leading t (r twards) a systemic cause: Prblem: SUV Mdel Z exhaust system rattles (A) Why? (Why des the exhaust system rattle?) Because f the exhaust pipe vibratin. (B) Why? (Why des the pipe vibrate?) Because the exhaust bracket is very clse t the supprt. (C) Why? (Why is bracket nw very clse t the supprt?) Because the line wrkers installed bracket in this lcatin. (D) Why? (Why did wrkers install bracket very clse t supprt?) Because specificatins stipulate this new lcatin. (E) Why? (Why did specs stipulate this lcatin?) 1. We dn t knw! Ntice this analysis crrectly mves backward in time, making clear the entire chain f events which led t the presently bserved prblem. 4. Use the THEREFORE test t check yur RCA series! The purpse f the THEREFORE test is fr the trubleshter t check the lgical flw f the causal chain frm the earliest pint in the sequence up t the present. After cmpletin f any causal chain, g t the earliest link reading each statement in turn with the wrd therefre between links. In the example abve this wuld becme: (D) The specificatins stipulated this lcatin
(C) The line wrkers installed the bracket in this lcatin (B) The bracket was t clse t the supprt (A) The exhaust pipe vibrates The mdel Z exhaust system rattles. [The Therefre tip cmes frm the Three Legged Five Whys technique as described in the 3L5W article.] Cnclusin The 5-Whys prcedure is nt an ANALYSIS tl. Yu need a cause analysis tl t use the 5-Whys prperly. The BPI Prblem Slving prcess is a pwerful tl fr finding cause. It answers the questin Why? and can be used when needed t prceed back int the past, dwn the causal chain, ne link at a time. Please click Cntact t let us knw what infrmatin yu might want abut BPI prducts and services. Or read mre abut ur BPI wrkshps related t prblem slving and tracking rt cause here: Systematic Prblem Slving Critical Thinking