Certified Six Sigma Black Belt Exam Voice of the Customer (VOC) 2 — Questions and Answers
Question 1: Which VOC data collection method is best suited for exploring unknown customer needs through open-ended discussion?
- Structured survey
- Focus group (Correct answer)
- Warranty claim analysis
- Control chart review
Correct answer: Focus group
Focus groups use facilitated discussion to uncover latent or unarticulated customer needs that structured methods might miss.
Question 2: In the Kano model, which category describes features that customers expect as baseline requirements and cause dissatisfaction only when absent?
- Attractive (Delighters)
- One-dimensional (Performance)
- Must-be (Basic) (Correct answer)
- Indifferent
Correct answer: Must-be (Basic)
Must-be (Basic) needs are taken for granted; their absence causes dissatisfaction but their presence does not increase satisfaction.
Question 3: A Black Belt wants to translate VOC data into measurable product requirements. Which tool is most appropriate for this translation?
- Pareto chart
- Quality Function Deployment (QFD) (Correct answer)
- FMEA
- Gauge R&R
Correct answer: Quality Function Deployment (QFD)
QFD (the House of Quality) systematically maps customer requirements to technical specifications and design parameters.
Question 4: What is the primary risk of relying exclusively on reactive VOC data such as customer complaints?
- It is too expensive to collect
- It overrepresents silent satisfied customers
- It captures only problems experienced, missing latent or unrealized needs (Correct answer)
- It cannot be converted to CTQs
Correct answer: It captures only problems experienced, missing latent or unrealized needs
Complaints represent customers who had a problem and chose to report it, leaving out unarticulated or future needs.
Question 5: Which metric directly measures the gap between customer expectations and perceived delivery in service quality research?
- Net Promoter Score (NPS)
- SERVQUAL gap score (Correct answer)
- Customer Effort Score (CES)
- Sigma level
Correct answer: SERVQUAL gap score
SERVQUAL measures five service dimensions and calculates the gap between expected and perceived service quality.
Question 6: During VOC analysis, a team identifies a need expressed as 'I want the report delivered fast.' What is the correct next step?
- Set the CTQ target at 24 hours immediately
- Probe further to define 'fast' with a specific, measurable threshold (Correct answer)
- Convert it directly to a control chart
- Archive it as an affinity diagram output
Correct answer: Probe further to define 'fast' with a specific, measurable threshold
Vague VOC statements must be probed and quantified before they can become valid, measurable CTQ characteristics.
Question 7: Which sampling approach is most appropriate when a company wants VOC input from distinct customer segments such as enterprise, mid-market, and small business?
- Simple random sampling
- Systematic sampling
- Stratified sampling (Correct answer)
- Convenience sampling
Correct answer: Stratified sampling
Stratified sampling ensures proportional or deliberate representation from each defined customer segment.
Which VOC data collection method is best suited for exploring unknown customer needs through open-ended discussion?