A Japanese factory owner taught his engineers a rule that any four-year-old already knows: when something goes wrong, ask “why?” five times.
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Ten items. Say your answer out loud before you reveal it.
Read the sentence, guess the meaning of the word in bold, then reveal.
The three words are: blame · assume · shortcut. Read each meaning, say the word, then reveal.
One missing word fits every phrase in the group. Say it, then reveal.
Read each part. After it, answer the quick check from memory, then discuss one question.
Sakichi Toyoda was born in 1867 in a village in Japan, the son of a carpenter. He grew up watching his mother and the other women of the village weaving cloth on hand looms, hour after hour, and he spent his life inventing machines to make that work lighter.
His most famous invention had an unusual feature: if a single thread broke, the loom stopped by itself. That sounds small. It changed everything. A machine that stops when something is wrong does not quietly produce a hundred metres of faulty cloth — it demands attention immediately.
The company he founded went on to make cars, and the family name became Toyota. But the habit of thinking behind that loom mattered even more than the machine: when something goes wrong, stop, and find out why it really happened.
1. What did Toyoda watch as a child?
2. What was unusual about his loom?
3. Why does a machine that stops itself matter?
1. Women weaving cloth on hand looms.
2. It stopped by itself when a thread broke.
3. Because the problem gets attention at once, instead of producing faulty work quietly.
Out of that habit came a rule that Toyota still teaches. When a problem appears, ask “why?” — and then ask “why?” about the answer. Five times is the usual number.
The classic example, told for decades inside the company, goes like this. The machine stopped. Why? A fuse blew because of an overload. Why? The bearing wasn't lubricated enough. Why? The oil pump wasn't pumping enough oil. Why? The pump shaft was worn. Why? There was no filter, so metal dust got in.
Look at the two possible repairs. Answer one gives you a new fuse — and the same breakdown next week. Answer five gives you a filter, and the problem never comes back.
The point is not the number five. The point is that the first answer is almost always a symptom, and that people stop asking far too early — usually as soon as they reach an answer that lets them blame somebody.
1. In the classic example, what was the first answer, and what was the fifth?
2. What is the difference between fixing answer one and answer five?
3. Why do people stop asking too early?
1. First: a fuse blew. Fifth: there was no filter, so metal dust got into the pump.
2. Answer one fixes it until next week; answer five stops the problem coming back.
3. Because they reach an answer that lets them blame somebody — and blame feels like an explanation.
The method escaped the factory long ago. Hospitals use it after a medical error. Software teams use it after a system fails. Schools use it when a policy isn't working. The Toyota rule for all of them is the same: keep asking until the answer is a system you can change, not a person you can punish.
It has real limits. Asking why five times gives you one chain, and most serious problems have several causes at once — which is why teams often draw a fishbone diagram first and then run the five whys down the biggest bone. The chain is also only as good as the people answering: ask a room full of colleagues who are frightened of blame, and you will get five polite answers and no truth.
Which may be the deepest lesson of the whole tool. The five whys is not really a technique. It is permission to keep asking an uncomfortable question after everyone else has decided the conversation is over.
1. What is the rule about where to stop asking?
2. Why do teams sometimes draw a fishbone diagram first?
3. What does the method need from the people in the room?
1. Stop when the answer is a system you can change, not a person you can punish.
2. Because most problems have several causes, and the five whys follows only one chain.
3. Honesty — if people are frightened of blame, the answers will be polite and useless.
One problem, five questions, one chain of causes. Each answer becomes the next question. You stop when you reach something you can actually change.
A school reports: students keep missing the Monday morning class. Below are five possible answers. Which level of “why” is each one — and which is the root cause to fix? Choose symptom (the surface), middle cause or root cause.
1. Root cause — a system you can change — fix this and the problem stops returning.
2. Symptom — this is the problem as it appears — the starting point, not a cause.
3. Middle cause — a step along the chain; ask why again.
4. Middle cause — closer, but it still doesn't explain why nobody noticed.
5. Symptom — still a description of what happened, not a cause.
6. Middle cause — a real reason for the behaviour — but the chain continues underneath it.
One chain, many causes. Serious problems rarely have a single line of causes; a fishbone diagram finds the others.
It follows the loudest answer. Five people can produce five different chains from the same problem.
Fear ruins it. If answering honestly gets someone into trouble, the chain stops at the first safe answer.
This tool is made of questions — and asking them well matters. A direct “Why did you do that?” sounds like an accusation. Indirect questions are softer, and reported questions let you tell the story afterwards.
Rewrite each direct question as an indirect one, starting with the words given.
1. Why did the delivery arrive late? → Could you tell me
2. Who checked the machine? → Do you know
3. Did anybody report the fault? → I'd like to know
4. Where are the safety records kept? → Could you tell me
1. …why the delivery arrived late?
2. …who checked the machine?
3. …whether (if) anybody reported the fault.
4. …where the safety records are kept?
The manager ran a five whys meeting yesterday. Report her questions.
1. “Why has the line stopped?” → She asked
2. “When did you last change the filter?” → She asked us
3. “Is there a checklist for this machine?” → She asked
4. “What will you do differently next month?” → She asked
1. …why the line had stopped.
2. …when we had last changed the filter.
3. …whether there was a checklist for that machine.
4. …what we would do differently the following month.
Now ask your teacher three indirect questions about this lesson — and then report what you asked.
Run your own chain of whys. Choose a task, start the timer, and talk. Use the polite question forms from the grammar tab.
Choose a problem that keeps coming back in your life or work. Ask why five times, out loud, and see where you land.
Take a problem in your town — traffic, litter, queues. Where does your chain of whys end?
Describe a time when a person was blamed for something that was really a system problem. What should have happened?