Lean Tools for Problem-Solving and Decision-Making
Just as is the case with any tool, it’s important to choose one that is “fit for purpose” (the right tool, for the right job). In this blog post, I’ll touch on these five tools, from the House of Lean:
- Ishikawa Diagramming
- Causal Loop Diagramming
- A3 Problem Solving
- Hoshin Kanri
- Value Stream Mapping
The tools that I describe here are organized from the easiest to use, to the most difficult to use, both from a facilitation point of view, and and also in terms of how long it takes to master and to use each tool. Or, to put it differently, the more strategic the area of focus is, or the more complex the problem domain, the higher the likelihood that a tool such as Hoshin Kanri or Value Stream Mapping might be the better choice, as shown in the illustration below.
Ishikawa (Fishbone) Diagramming
What is it?
A visual root cause analysis tool
When to use it?
To visually portray potential causes of a problem
How to use it?
- Agree on a problem statement — identify the problem to be solved; that is, the “effect”. (Missed Free Throws, in the example diagram below.)
- Come up with a list of categories, for causes behind the problem — Write out the causal categories, where each one is at the end of one of the nodes (at the end of “fishbones”).
- For each of those causal categories, think of all of the possible causes for the problem that fit under that category — Write each of the causes as smaller “fishbones” off of that larger fishbone. (Another way to put it: keep asking “why”.)
- Continue to iterate — If there is nesting (causes inside of causes), continue to add smaller fishbones, as necessary.
Causal Loop Diagramming
What is it?
A visual technique for showing an interconnected series of causal relationships.
When to use it?
To more deeply delve into the interrelationships between parts of a system or subsystem and how those are manifested
How to use it?
- Identify the key variables in a system — what are the “nouns”?
- Indicate the causal relationships between the variables via links — what are the “verbs”?
- Show how the variables are interconnected — what are the causal relationships?
- Understand the system as a whole — what type of behavior does the system produce?
Note: Causal Loop Diagramming has a particular set of conventions for notation, as shown in the example below. See also the sample Causal Loop Diagram.
What are some things that the Causal Loop Diagram above tells us?
- When work isn’t prioritized well, more work is taken on
- As more work is taken on, ability to deliver suffers
- As pressure to deliver increases, work tends to show up in large batches, which get increasingly difficult to deliver, in the face of growing technical debt
- Keep team members focused on and dedicated to the work that team is responsible for (which is often product-focused)
- Don’t pressure teams to increase the pace they are working at simply because unrealistic deadlines (with fixed scope) were set up front; velocity is a measure of capacity, not productivity
- If we don’t set aside time for code refactoring and addressing technical debt, the ability of the team to maintain the code base becomes increasingly difficult
- Keep Brook’s Law in mind — adding people to a team does not magically make a team produce more (in fact, it initially slows them down)
A3 Problem Solving
What is it?
A structured means of describing a problem & solution, in a standardized format
When to use it?
When you want to explore multiple ways to solve a problem, and have both transparency and buy-in on a way to address the problem
How to use it?
- Background & problem statement — what is the nature of the issue?
- Current reality — what can we observe about the problem to make sure we understand it and describe it accurately?
- Target condition — what does the desired future state look like?
- Steps, Schedule & Measurements — what steps are needed to get to the target condition and how do we know when we’ve arrived?
A3 Problem Solving Quadrants
It can be helpful to think of the A3 Problem Solving process as one which flows according to the following four quadrants:
A3 Problem Solving Example
Part of the appeal of A3 Problem Solving is the consistent format of the output, an example of which is shown below. Notice how the reader’s eye is directed to the series of boxes, in a particular order. A3 Reports tend to look much like this, regardless of which area is being analyzed.
Note: This technique is called “A3 Problem Solving” is that the resulting output can fit on a single sheet of paper (in Europe, A3 is a common paper size).
For a deeper dive into A3, see my blog post Digging Into Problems with A3.
Hoshin Kanri
What is it?
Also known as “Strategy Deployment”, Hoshin Kanri seeks to ensure that activities at all levels of the organization (Strategy, Tactics, and Operations) are working in concert, to reduce or eliminate the waste often associated with poor communications and lack of organizational alignment
When to use it?
Hoshin Kanri tends to be most helpful at major inflection points, such as planning for a new fiscal year or for a major strategic initiative
How to use it?
- Create a strategic plan — which goals should we focus on achieving? (no more than five)
- Develop tactics — what should business plans look like at the tactical (team) level to align with the strategic plan?
- Take action — what are the operational activities that align with the strategic plan and the tactics? (this is the operational, or “Gemba”, level
- Review and adjust — How often do we need to check in in on to adjust the plan to reflect new information such as a changing business landscape?
Hoshin Kanri Quadrants of Growth
It can be helpful to think about quadrants of growth similar to those shown below when using Hoshin Kanri, where “jobs” refer to anything that needs to be done on behalf of a customer, and “consumer” vs. “non-consumer” is a distinction that helps mark a boundary between existing product offerings, versus truly new product offerings.
Hoshin Kanri Information Flow
Much as is the case with A3 Problem Solving, outputs from Hoshin Kanri tend to use a specific format, where the information flows in a particular order, as shown below.
Hoshin Kanri Planning Matrix
A completed Hoshin planning matrix is shown in the example below.
Value Stream Mapping
What is it?
A means of surfacing areas of waste that exist in any value stream or value stream segment
When to use it?
To gain a detailed understanding of the work that an organization does and idea areas for focusing improvement efforts
How to use it?
- Establish scope — what part of the value stream do we plan to focus on?
- Identify process steps — what are the main activities that need to happen?
- Identify roles & groups — who’s involved with each of the major process steps?
- Identify improvements — what changes should we consider to streamline the process?
- Calculate totals — analyze the numbers associated with each of the process steps and the value stream segment as a whole to provide greater insight
- Prioritize and initiate improvements — decide which areas to focus on and make a plan
Note: Value Stream Maps have two main areas of focus: 1. the current state; 2. the future state (see the examples below).
Value Stream Mapping Notation
Value Stream Mapping uses the notation below.
Conclusion
The instructions in this blog post are intentionally concise, intended to provide just enough information about each technique to know whether it is a potential fit for a particular situation. For detailed information about the more complex techniques in particular, see the many books, articles, and blog posts that are available about each of them.
