Quality tools
Why Do I Keep Making the Same Mistakes at Work?
Examine one recurring mistake, separate evidence from possible explanations, and test a change using a fictional report example.
Read the practical guide →Problem solving · Lean Six Sigma practice
Use the tools with a clear question and evidence.
Practical guides to choosing a method, interpreting what it shows, and deciding what to check next. Each article includes an original, clearly labeled fictional example and links to its sources.
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Quality tools
Fishbone Diagram and 5 Whys: What to Do Next
Check possible causes, use 5 Whys on a supported line of inquiry, then test and monitor a change.
Read the practical guide →Quality tools
Pareto Chart Frequency vs Cost: A Worked Example
Compare Pareto charts by frequency and cost using one fictional dataset. Calculate percentages, see why priorities change, and choose what to investigate.
Read the practical guide →Lean and A3
A3 Problem Statement Examples: How to Write a Clear Statement
Write an A3 problem statement with a measurable target-versus-actual gap. Follow a fictional worked example and improve weak statements without guessing causes.
Read the practical guide →Statistics and evidence
Statistical Test for Before and After Data: A Practical Guide
Choose a before-and-after statistical test using your data type and study design. Compare paired t-tests, independent samples, proportions, and key limits.
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