CLL Waste Identification & Process Improvement 3 — Questions and Answers
Question 1: A Lean practitioner discovers that 40% of a team's daily effort is spent correcting errors found downstream. Which category of waste is most prominently driving total lead time?
- Waiting
- Defects (Correct answer)
- Inventory
- Transportation
Correct answer: Defects
Defects require rework or scrap, consuming resources and extending lead time without adding value to the customer.
Question 2: In lean process improvement, 'Takt Time' is calculated as:
- Total production time divided by total units produced
- Available production time divided by customer demand rate (Correct answer)
- Customer demand rate divided by available production time
- Cycle time minus wait time per unit
Correct answer: Available production time divided by customer demand rate
Takt Time = Available Production Time ÷ Customer Demand, setting the rhythm at which products must be completed to meet demand.
Question 3: Which of the following is NOT one of the original 7 wastes (Muda) identified by Taiichi Ohno?
- Transportation
- Non-Utilized Talent (Correct answer)
- Waiting
- Defects
Correct answer: Non-Utilized Talent
Non-Utilized Talent was added later (making 8 wastes total); Ohno's original 7 did not include it.
Question 4: A process improvement team uses a spaghetti diagram during a gemba walk. What specific waste are they most likely trying to quantify?
- Overproduction
- Defects
- Excess Inventory
- Motion (Correct answer)
Correct answer: Motion
A spaghetti diagram traces the physical movement paths of people or materials to measure and visualize motion waste.
Question 5: Which Lean concept refers to the practice of stopping production immediately when a defect is detected, preventing it from moving downstream?
- Andon
- Jidoka (Correct answer)
- Heijunka
- Muri
Correct answer: Jidoka
Jidoka (autonomation) empowers workers or machines to stop the line the moment a defect occurs, building quality at the source.
Question 6: In the DMAIC improvement cycle, at which phase would a team primarily use a fishbone (Ishikawa) diagram?
- Define
- Measure
- Analyze (Correct answer)
- Improve
Correct answer: Analyze
The Analyze phase uses tools like fishbone diagrams to identify root causes of defects or process problems.
Question 7: A team reduces batch size from 100 units to 10 units. Which immediate improvement in waste reduction is most likely to occur?
- Reduced defect rate per unit
- Reduced work-in-process (WIP) inventory (Correct answer)
- Increased machine utilization
- Reduced takt time
Correct answer: Reduced work-in-process (WIP) inventory
Smaller batches reduce the amount of work-in-process sitting between operations, lowering inventory waste and shortening lead time.
CLL Waste Identification & Process Improvement 3
A Lean practitioner discovers that 40% of a team's daily effort is spent correcting errors found downstream.
Which category of waste is most prominently driving total lead time?