- The Fishbone Diagram is a root cause analysis that assists in accurately identifying the causes of an effect, event, or problem.
- The Fishbone Diagram is a collaborative and thorough five-step process involving teams of employees.
- To be effective, the Fishbone Diagram technique requires a diverse range of perspectives and the ability to correctly identify the most likely causes.
The Fishbone Diagram is a diagram-based technique used in brainstorming to identify potential causes for a problem, thus it is a visual representation of cause and effect. The problem or effect serves as the head of the fish. Possible causes of the problem are listed on the individual “bones” of the fish. This encourages problem-solving teams to consider a wide range of alternatives.
Understanding the Fishbone Diagram
A Fishbone Diagram is simply a visual representation of cause and effect. The problem or effect serves as the head of the fish.
Possible causes of the problem are listed on the individual “bones” of the fish and where possible, are grouped into categories on each bone.
Through the use of categories, Fishbone Diagrams encourage problem-solving teams to consider a wide range of alternative, less-obvious causes.
Cause and effect diagrams can also:
- Help businesses understand where or why a process is not working.
- Be used in product development where the product concerned is intending to solve a consumer problem.
- Identify potential problems before they arise, such as the teething problems associated with new product launches.
For example, Mazda used the Fishbone Diagram to design their now iconic MX-5 sportscar.
Engineers even used the diagram to identify that the current design of the door would not allow the driver to rest their arm on it while driving.
How to use the Fishbone Diagram
Using the Fishbone Diagram in practice is relatively simple, but the technique is nevertheless a powerful way to unearth causes to problems.
Teams of employees should follow this 5-step process:
Define the problem, and then write it at the mouth of the fish
The problem itself should as clear and concise as possible. Make sure there is an agreement between all team members before proceeding.
Define the categories of causes, and then write them along the bones of the skeleton of the fish
Categories will vary from industry to industry, but common categories include the environment, procedure, human resourcing, and equipment.
Brainstorm potential causes
Begin with the question “Why does this happen?” and then write each response as a branch of the relevant category.
Probe further
For the answers gleaned in step 3, ask the same question once more. These “sub-causes” can be written as secondary branches and are particularly important for large or complex causes that need further investigation.
When the group has run out of ideas, it’s time to investigate the causes in more detail.
Look for causes that appear more than once but with slightly different wording.
Employee or consumer surveys can also be used to verify the validity of particular causes.
Fishbone Diagram best practices
Creative a diverse team
Although the temptation may be to create a team who has direct experience with the problem, it’s more beneficial to include other employees too.
Outside employees who do not directly deal with the problem can bring a balanced, unbiased, and objective stance.
Clarify the major cause categories
In business and marketing, the 8 Ps of product marketing is a good place to start. In other words: product, price, place, promotion, personnel, process, physical evidence, and performance.
Keep it (relatively) simple
Fishbone Diagrams with many potential causes quickly become cluttered and confusing. Consider asking each member of the team to vote for their four most probable causes.
From there, choose the four categories that received the most votes and begin the process.
Fishbone diagram examples
Supermarket chain
In the first example, consider a supermarket chain that wants to determine the probable causes of items that are delayed, damaged, or incorrect once delivered to its stores.
On the fishbone diagram, the team describes the main problem at the mouth of the fish.
They write the following: “Items that are incorrectly picked in the warehouse, experience delayed delivery, or are damaged in transit”.
Next, the team defines five problem cause categories and answers the question “Why does this happen?” for each:
- Materials – improper packing material, wrong product received from warehouse or from supplier.
- Personnel – product mishandling, negligence, human error, a shortage of truck drivers.
- Measurements – incorrect delivery time estimate.
- Environment – heat, humidity, and rain damage, poor road quality.
- Machines – improper delivery vehicle, improper use of a forklift to unload items, faulty or unreliable inventory management system.
As per step three in the process, the team then probes further by asking the question of “Why does this happen?” once more to identify sub-causes.
For example:
- Improper packing material – cheaper materials are used to save time and money.
- Product mishandling – employees are not trained in the correct way to handle stock and, in any case, are not motivated to protect company property.
- Incorrect delivery time estimate – deliveries are sent out during peak hour traffic, which frequently causes delays.
- Heat damage – perishable items such as chocolate are not transported in trucks with refrigeration.
- Unreliable inventory management system – old, outdated, and not upgraded due to cost constraints.
Software subscription
In the second example, let’s repeat the process with a software company that realized 55% of its users were canceling their subscription after the first month.
With the core problem identified, the team then considered the processes that were likely contributing to the issue.
Four key areas were identified, with some theoretical problem causes listed for each:
- Users – a lack of awareness concerning the full benefits of the software, lackluster customer support, user onboarding problems, and a tendency to not use the software consistently.
- Software – software is difficult to use, software is buggy or unstable, installation requires several additional plugins, and full functionality requires additional payment.
- Subscription system – a lack of payment options, credit card expiry dates voiding automatic renewal, a lack of reminders that payment is imminent, and a payments interface that is not user-friendly.
- Marketing – the absence of relationship marketing initiatives, a lack of rewards or incentives for repeat subscribers, and the ability to keep the product or service top-of-mind among consumers.
Now let’s take a look at some potential sub-causes that the team must then evaluate to determine how each affects customer retention:
- Lackluster customer support – inadequate training of the customer support team.
- Software usability issues – the product was rushed to market before it was ready.
- A lack of reminders that payment is imminent – a somewhat outdated belief that businesses should not contact customers unnecessarily.
- The absence of relationship marketing initiatives – an inexperienced marketing team that does not realize the power of relationship marketing as a tool to foster customer retention.
Manufacturing Defects
In this scenario, a manufacturing company wants to address the issue of increasing defects in their products. The core problem stated at the mouth of the fish is, “Increase in product defects.”
The main problem is then broken down into several categories:
- Materials: Poor-quality raw materials, incorrect specifications.
- Manpower: Lack of training, inadequate skills, insufficient workforce.
- Methods: Outdated manufacturing processes, lack of quality control.
- Machines: Malfunctioning equipment, lack of maintenance, outdated machinery.
- Measurement: Inaccurate testing equipment, inconsistent quality checks.
For each category, sub-causes are identified:
- Lack of training: Inadequate budget allocated for employee training.
- Outdated manufacturing processes: Resistance to change among long-time employees.
- Malfunctioning equipment: Irregular maintenance schedule.
- Inaccurate testing equipment: Lack of calibration.
Customer Complaints
Imagine a telecommunications company facing a significant increase in customer complaints regarding network connectivity issues. The core problem stated on the fishbone diagram is, “Rising Network Connectivity Complaints.”
The problem is further dissected into categories:
- Network Infrastructure: Equipment failure, outdated technology.
- Customer Devices: Incompatibility, device issues.
- Service Providers: Third-party network problems, lack of communication.
- Environmental Factors: Weather-related disruptions, geographic challenges.
- Maintenance: Irregular maintenance schedules, lack of preventive measures.
Sub-causes for each category are identified:
- Equipment failure: Lack of redundancy in critical network components.
- Incompatibility: Failure to update device compatibility lists.
- Third-party network problems: Insufficient collaboration with third-party providers.
- Weather-related disruptions: Lack of weatherproofing in critical infrastructure.
- Irregular maintenance schedules: Failure to implement a proactive maintenance calendar.
Employee Turnover
A software development company is concerned about a high rate of employee turnover. The core problem in the fishbone diagram is, “High Employee Turnover Rate.”
The problem is categorized into several areas:
- Work Environment: Lack of work-life balance, stressful work conditions.
- Compensation: Below-average salaries, inadequate benefits.
- Management: Ineffective leadership, lack of career growth opportunities.
- Workload: Overwhelming project demands, unrealistic deadlines.
- Hiring Process: Insufficient screening, poor onboarding.
Sub-causes for each category are determined:
- Lack of work-life balance: Expectation of working long hours without adequate breaks.
- Below-average salaries: Failure to conduct regular salary reviews.
- Ineffective leadership: Lack of management training programs.
- Overwhelming project demands: Inaccurate project estimations.
Website Traffic Drop
A digital marketing agency is dealing with a sudden drop in website traffic for one of its clients. The core problem stated at the head of the fishbone diagram is, “Significant Drop in Website Traffic.”
The problem is divided into the following categories:
- Content: Poor-quality content, lack of fresh updates.
- SEO Strategy: Algorithm changes, outdated SEO tactics.
- Technical Issues: Slow page loading, broken links, server downtime.
- Competitive Landscape: Increased competition, similar content saturation.
- Marketing Efforts: Reduced ad spend, lack of social media engagement.
Sub-causes for each category are explored:
- Poor-quality content: Reliance on outdated content creation methods.
- Algorithm changes: Lack of adaptability to search engine algorithm updates.
- Slow page loading: Insufficient hosting resources.
Key takeaways
- Fishbone Diagram Overview: The Fishbone Diagram, also known as the Ishikawa Diagram or Cause-and-Effect Diagram, is a visual tool used for problem-solving and analysis. It was developed by Kaoru Ishikawa, a Japanese quality control expert. The diagram gets its name from its appearance, resembling the skeletal structure of a fish. It provides a structured and systematic approach to understanding the relationship between a specific problem or effect and its potential causes.
- Components of a Fishbone Diagram:
- Head of the Fish: At the “head” of the fish, the problem or effect that needs analysis is written. This central element represents the issue being investigated.
- Bones of the Fish: Extending from the head, the “bones” represent different categories or areas that could contribute to the problem. These categories are usually identified as major factors influencing the problem.
- Purpose and Benefits:
- The Fishbone Diagram is a powerful tool for brainstorming and problem-solving because it helps teams explore a wide range of potential causes systematically.
- By visually representing the cause-and-effect relationships, the diagram enables teams to understand the complexities of a problem and identify both obvious and less-obvious contributing factors.
- Application of Fishbone Diagrams:
- Operational Processes: Businesses can use Fishbone Diagrams to identify factors causing inefficiencies or breakdowns in their processes. By examining categories such as people, processes, technology, and materials, organizations can pinpoint root causes and improve their operations.
- Product Development: In product design and development, Fishbone Diagrams can reveal issues affecting product quality. By analyzing factors related to design, manufacturing, materials, and human factors, teams can enhance product performance and user satisfaction.
- Risk Management: The diagram can help anticipate potential problems before they occur. By identifying causes that could lead to future issues, organizations can take preventive measures to minimize risks.
- Example: Mazda’s Use of Fishbone Diagram:
- In the context of Mazda’s MX-5 sports car design, engineers used the Fishbone Diagram to explore potential design flaws that might affect the driving experience.
- Categories like ergonomics, design details, and user preferences were considered to identify potential areas for improvement.
- The diagram allowed Mazda’s team to address issues early in the design process and create a more user-friendly and appealing product.
- Steps to Create a Fishbone Diagram:
- Step 1: Define the Problem: Clearly articulate the problem or effect that needs analysis. Write it at the head of the fish.
- Step 2: Identify Categories: Define the major categories of causes that could contribute to the problem. These categories will vary based on the context of the problem.
- Step 3: Brainstorm Potential Causes: Within each category, brainstorm potential causes by asking “Why does this happen?” Write down all possible causes.
- Step 4: Probe Further: For each potential cause identified in step 3, ask “Why does this happen?” again to dig deeper and identify sub-causes or contributing factors.
- Step 5: Investigate and Validate: Research or survey to validate the potential causes and their impact. Determine which causes are most likely contributing to the problem.
- Best Practices for Using Fishbone Diagrams:
- Diverse Team: Assemble a team with a variety of perspectives and expertise. This diversity ensures comprehensive analysis and reduces bias.
- Clear Categories: Define clear and relevant categories that align with the problem. This helps guide the brainstorming process and keeps it organized.
- Simplicity: Avoid overcrowding the diagram with too many potential causes. Prioritize the most significant causes and sub-causes to maintain clarity.
- Examples of Fishbone Diagrams:
- Supermarket Chain Example: In this scenario, a supermarket chain aims to identify why items experience delays, damage, or incorrect delivery. Categories like materials, personnel, measurements, environment, and machines are considered, each leading to potential sub-causes.
- Software Subscription Example: For a software company facing high subscription cancellations, categories such as users, software, subscription system, and marketing are explored. Sub-causes within each category are investigated to identify root causes.
- Key Takeaways:
- The Fishbone Diagram is a versatile tool applicable to various industries and scenarios.
- Its systematic approach encourages comprehensive problem analysis and solutions.
- Effective use of Fishbone Diagrams requires collaboration, clear categorization, and validation of potential causes to address underlying issues successfully.
Connected Analysis Frameworks
Failure Mode And Effects Analysis
Other related business frameworks:
- AIDA Model
- Ansoff Matrix
- Business Analysis
- Business Model Canvas
- Business Strategy Frameworks
- Blue Ocean Strategy
- VRIO Framework
Additional resources: