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Five Whys

Last updated: 6 April 2023

Five Whys illustration
Ask why fives times to find the root cause

The five whys process is a tool used to analyze the cause and effect of a problem systematically. By asking multiple "why" questions, it can help identify root causes and develop solutions to them.


Sakichi Toyoda, the founder of Toyota Motor Company, developed the five whys approach. The process was initially used as part of the company’s problem-solving approach, known as the Toyota Production System, to eliminate waste and improve efficiency.

How it works

The five whys approach is an iterative process where you start with the identified problem or symptom, then ask “why” questions to try and uncover its root cause. You then repeat this process five times to drill down several levels into the underlying cause of the problem. For example, if your original problem statement is “the project is behind schedule,” you might ask why? The answer might be, “The team is not meeting deadlines,” so you could ask why again until you get to the deeper reason why something isn’t working.

How to use it

Using the five whys approach effectively helps to create a timeline for each question. The five whys will help you track which causes are related to which problems and make it easier for everyone involved in the discussion to stay focused. Additionally, all stakeholders need to be involved in this conversation and contribute their insights during each iteration.


For example, let's say your team has been having difficulty meeting customer service goals. To figure out why using five whys, break down each potential cause with a why question and try to identify solutions along the way:

  1. Why are we having trouble meeting customer service goals? Because our team isn't responding quickly enough
  2. Why isn't our team responding quickly enough? Because they're overwhelmed due to the high call volume.
  3. Why is there high call volume? Because customers aren't finding answers through our website or social media channels.
  4. Why aren't customers finding answers through our website or social media channels? Because we haven't updated them with new FAQs.
  5. Why haven't we updated them with new FAQs? Because we haven't had time due to other priorities.

In this example, the solution would be to prioritize updating customer service FAQs on your website so customers can find answers quickly without needing support from your team.


  • The five whys approach involves asking a series of "why" questions about a given problem to uncover its root causes.
  • It helps bring clarity between symptoms and solutions by allowing stakeholders to come together and brainstorm ideas collaboratively.
  • Create a timeline for each question so that everyone stays focused on finding root causes and potential solutions quickly.


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