5 whys template
The 5 whys is a quick way to find the root cause of a problem: state the problem, ask why it happened, ask why again of that answer, and keep going until you reach a cause you can change. This free Word template puts the chain on one page, with a column for the evidence behind each answer, room for a second branch, and the actions that follow.
Running a company of 30 to 200 people? Documents like this are now worth money.
Use it on a single, contained problem, such as invoices that keep going out late or a machine that trips every Monday. Bigger or more serious problems need a full root cause analysis.
What's in the template
5 whys analysis
| Problem | One sentence, with a number if you have one |
|---|---|
| Where and when | |
| How it was noticed | |
| Facilitator | |
| People taking part | Include someone who does the work |
| Date |
The why chain
Ask why of the problem, then of each answer. Note the evidence for every answer; if there's none, check before going on. Stop at a cause you can change.
| # | Why did this happen? | Answer (a fact, not a name) | Evidence or how to check |
|---|---|---|---|
| 1 | |||
| 2 | |||
| 3 | |||
| 4 | |||
| 5 | |||
| 6 |
Second branch
Use this when one answer turns out to have two separate causes.
| # | Why? | Answer | Evidence |
|---|---|---|---|
| 2b | |||
| 3b | |||
| 4b |
Root cause
- It names a process, system, design or management cause, not a person
- Every step back to the problem is backed by evidence
- Reading the chain backwards with 'therefore' makes sense
Actions
| Action | Owner | Due | How we'll know it worked |
|---|---|---|---|
Follow-up
| Review date | |
|---|---|
| Has the problem come back? | Yes or no |
| Need a fuller analysis? | e.g. a fishbone diagram or a full root cause analysis |
How to run a 5 whys session
- Write the problem down as something you observed, with a number where possible: "client invoices went out on the 9th working day in four of the last six months", not "billing is slow".
- Get three to six people together for half an hour, including someone who does the work, ideally where the problem happens.
- Ask why, and write the answer as a fact, with the evidence next to it. If nobody knows, check rather than guess.
- Split the chain when an answer has two causes. HSE's investigation workbook asks why of every reason on a line, and keeps asking until the answers are no longer meaningful, so its version branches naturally.
- Stop at a cause you can act on. That might take three whys or seven. NHS England's improvement guide treats five as a rule of thumb, not a target.
- Read it backwards with "therefore". If "no remote access, therefore timesheets are late, therefore approval is late" holds up, the chain is sound.
- Give the root cause an action, an owner and a date, and check later that the problem has stopped.
Where it comes from, and its limits
The technique is associated with Toyota and the Toyota Production System. NHS England's quality improvement guide describes it as devised by Toyota while the company developed its manufacturing methods; it has long since spread beyond car making. It's fast and needs no software, but it has three weaknesses:
- It follows one causal chain. Most real problems have several causes, and a single line of whys picks one path and hides the rest. Branch the chain, or start with a fishbone diagram to see the whole field first.
- It stops at blame. The easiest answer to "why?" is a person: "because Dan didn't check". OSHA's guide for employers warns that an investigation focused on finding fault will always stop short of the root causes. When an answer names a person, ask why the process let it happen.
- It only knows what the room knows. Answers can be opinions, and two groups can follow different chains from the same problem. The evidence column guards against both.
The same NHS guide calls it a very basic tool, and says it isn't suitable as the key technique when investigating an incident that arises from a complex system.
Example: late invoices at a fictional consultancy
A 5 whys from a fictional 35-person engineering consultancy whose invoices kept going out late:
| # | Why? | Answer | Evidence |
|---|---|---|---|
| 1 | Why do invoices go out on the 9th working day? | Billing waits for project managers to approve the month's time | Approval dates in the timesheet system |
| 2 | Why is time approved late? | Site engineers' timesheets arrive after month-end | 11 of 18 submitted after the 1st |
| 3 | Why do they arrive late? | Engineers can only enter time from the office | The system runs on the office network only |
| 4 | Why only from the office? | Remote access was never switched on at installation | The supplier confirms a mobile app exists |
| 5 | Why not? | Nobody owned the timesheet process, so nobody asked | No process owner in the operations manual |
At step 2 someone first answered "because the project managers are disorganised". The team set that aside and asked what made late approval possible. Actions: switch on the mobile app; make the finance manager the process owner; set a noon cut-off on the last working day with an automatic reminder. Check: invoices out by the 3rd working day for three months running.
Common mistakes
- A vague starting problem, such as "communication issues", which lets the answers wander.
- Answers with no evidence. An answer nobody can check is a hypothesis; test it before building on it.
- Ending on a person or on "human error". Keep asking why the system allowed it.
- Forcing exactly five, either padding the chain or stopping a step short.
- Jumping to a solution, such as "because we haven't bought the new system": a wish, not a cause.
- Never checking the result, so nobody knows whether the root cause was right.
Frequently asked questions
Do you have to ask why exactly five times?
No. Five is a rule of thumb. Stop when you reach a cause that you can change and that would stop the problem if it were fixed, whether that takes three whys or seven.
Is the 5 whys the same as root cause analysis?
It's one root cause analysis technique, and one of the simplest. A full analysis adds a timeline, several causes tested against evidence, and a check that the fix worked. The root cause analysis template covers all of that.
Can you use the 5 whys with a fishbone diagram?
Yes. The fishbone lists every possible cause under headings such as people, methods and equipment; you then run a 5 whys on the two or three causes the evidence supports. NHS England's guide suggests the same pairing.