Net Promoter Score (NPS)

Introduction: NPS in Lean Context

The Net Promoter Score (NPS) is a simple but powerful customer feedback metric that measures loyalty and satisfaction. In a Lean context, NPS is used to understand how well processes deliver value from the customer’s perspective — a core principle of Lean thinking focused on continuous improvement and customer focus.

Background

Developed by Fred Reichheld in 2003, NPS was designed to measure customer loyalty through a single question:
“How likely are you to recommend our company/product/service to a friend or colleague?”
Customers respond on a scale from 0 to 10. Their answers are grouped into three categories:

• Promoters (9–10): Loyal customers who actively recommend.
• Passives (7–8): Satisfied but unenthusiastic customers.
• Detractors (0–6): Unhappy customers who may damage brand reputation.

In Lean management, NPS is not only a marketing metric but also a Voice of the Customer (VoC) tool that helps identify waste, bottlenecks, and process failures from the customer’s viewpoint.

Key Elements / Features

• Purpose: Measure customer satisfaction and loyalty in one metric.

Formula:

\(
\text{NPS} = \% \text{Promoters} – \% \text{Detractors}
\)

• Scale: Ranges from -100 to +100. A positive score indicates more promoters than detractors.
• Interpretation:
  • Above +50 = excellent
  • 0 to +50 = good
  • Below 0 = needs improvement
• Link to Lean: Helps identify gaps between customer expectations and process performance.

Applications / Examples

• Lean Service Processes: Measuring satisfaction after service improvements.
• Manufacturing: Tracking customer feedback after product quality enhancements.
• Healthcare: Assessing patient satisfaction post process redesign.
• Education: Evaluating training programme effectiveness or learner engagement.

Example:
A service company surveys 100 customers.

• 60 rate 9–10 (Promoters)
• 25 rate 7–8 (Passives)
• 15 rate 0–6 (Detractors)

\(
\text{NPS} = 60\% – 15\% = +45
\)

An NPS of +45 shows strong customer loyalty, but Lean teams can still explore why 15% are dissatisfied.

Relevance / Impact

In Lean, NPS serves as a direct indicator of how effectively value flows to the customer. By linking customer feedback with process metrics, teams can prioritise improvements that have the greatest impact on satisfaction and loyalty. Continuous monitoring of NPS helps sustain a culture of customer focus and Kaizen.

See also

• Voice of the Customer (VoC)
• Customer Value
• Value Added (VA)
• Critical to Quality (CTQ)