Certified Quality Engineer (CQE) Practice Exam 2025 - Comprehensive All-in-One Study Guide for Exam Success!

A quality control chart is a tool used in statistical quality control to monitor and improve the stability and performance of a manufacturing or business process. One of its fundamental characteristics is that it tracks process variability over time, allowing for the identification of trends or shifts in process behavior. By plotting data points over a series of measurements, quality control charts enable organizations to determine whether the process is in control or if there are indications of potential issues that need to be addressed.

This monitoring of variability can help ensure that processes remain consistent and produce products or services that meet quality specifications. Engineers and practitioners can use this information to make informed decisions about process adjustments or improvements, thereby enhancing overall quality.

The other options do not accurately describe the primary purpose and function of a quality control chart. For example, it does not focus solely on qualitative data, nor is it a tool for marketing analysis or evaluation of employee performance metrics. Its primary application lies in understanding and managing process quality over time.