Which metric is NOT related to user behavior?

The error rate is not directly related to user behavior, as it primarily measures the performance and reliability of an application rather than how users interact with it. While user behavior metrics focus on engagement and interactions within the application—such as the number of active sessions, the rate at which users leave without further interaction (bounce rate), and the number of actions taken during a session—the error rate is centered around identifying issues that impact the application’s functionality and performance. High error rates may indicate problems that need resolving but do not provide insights into user engagement or satisfaction. Thus, it stands apart from the metrics that reflect user behavior.