Voice of the Process

What is Voice of the Process (VOP)?

Voice of the Process (VOP) is a foundational concept in Six Sigma and quality management. It represents the actual performance data and capabilities of a process. Put simply, VOP tells you what a process is really doing right now: whether it's under control, and how much variation shows up in its outputs. Unlike customer requirements or business goals, VOP reflects reality based on measurable data.

In practice, VOP acts as a bridge between the Voice of the Customer (what customers need) and the Voice of the Business (what the organization wants to achieve). By digging into VOP data like cycle times, defect rates, and process variability, organizations can figure out whether their processes are actually capable of meeting customer expectations. This analysis often reveals opportunities for process improvement that might otherwise go unnoticed.

VOP gives you insights into process stability, capability, and control limits. When VOP falls within acceptable customer specifications, the process is considered capable. When it exceeds customer tolerances, that's a signal that improvement work is needed to close the gap between actual performance and required standards.

Key Characteristics of Voice of the Process

• Data-Driven Measurement: VOP relies on quantifiable metrics collected from actual process performance. This includes cycle time, throughput, error rates, and statistical process control data.
• Process Control Limits: VOP establishes upper and lower control limits (UCL and LCL) that define the natural variation range of the process. These limits help distinguish normal variation from special causes.
• Dynamic and Continuous: VOP values change with each new data point, offering real-time insights into process behavior and enabling teams to spot problems or trends early.
• Capability Assessment: VOP reveals whether a process can consistently meet customer specifications by comparing actual performance against required tolerances.
• Baseline for Improvement: VOP establishes where process performance stands today, serving as a baseline to measure the effectiveness of continuous improvement initiatives.

Voice of the Process Examples

Example 1: Hospital Wait Time Analysis

A hospital emergency department ran a four-week study to measure patient wait times. The VOP data showed an average wait time of 8 minutes with a standard deviation of 1 minute. Control charts revealed that the process was stable with predictable variation. But here's the catch: when compared to the Voice of the Customer (patients expecting a 5-minute wait), the VOP indicated that the current process couldn't meet customer requirements. That finding triggered a process improvement project.

Example 2: Manufacturing Quality Control

A manufacturing facility producing precision components measured VOP through defect rates and dimensional accuracy. The process was generating a defect rate of 3.5% with part dimensions varying between 0.02mm and 0.08mm from specification. Statistical analysis showed the process was in control but not capable of achieving the customer requirement of less than 1% defects. This VOP data guided the team to implement standard work procedures and equipment calibration protocols to reduce variation.

Example 3: Call Center Performance

A customer service call center tracked VOP metrics including average handle time (AHT) of 6.2 minutes, first-call resolution rate of 78%, and customer satisfaction scores averaging 7.8 out of 10. Control charts showed the AHT was stable, but the resolution rate exhibited special cause variation on certain days. This VOP data helped identify specific training gaps and process bottlenecks that were keeping the team from achieving the customer expectation of 90% first-call resolution.

Voice of the Process vs Voice of the Customer

Understanding the relationship between VOP and Voice of the Customer (VOC) is essential for effective process management and improvement.

When VOP falls within VOC specifications, the process is meeting customer requirements. When VOP exceeds VOC tolerances, a performance gap exists that requires process improvement initiatives to address.

How Glitter AI Helps with Voice of the Process

Glitter AI helps teams capture and communicate Voice of the Process insights through visual process documentation. By creating video-based standard operating procedures and work instructions, organizations can document the actual steps and variations in their current processes. This makes VOP data more accessible and actionable for improvement teams.

When process improvement initiatives launch based on VOP analysis, Glitter AI enables teams to quickly update documentation to reflect new procedures. This ensures that improvements are standardized and sustained over time. The platform's visual documentation capabilities help bridge the gap between VOP metrics (the numbers) and actual process execution (how work gets done), creating a feedback loop that supports continuous process refinement and capability enhancement.