In the era of microservices and big data, monitoring data is a crucial tool that enhances testing and overall software quality by providing insights into customer behavior, identifying the impact of bugs, and refining testing priorities. The use of monitoring systems has significantly influenced the author's work as a Quality Director, enabling a deeper understanding of the product and its users. For example, monitoring data can reveal unexpected user preferences, such as the continued popularity of the Opera browser, which can affect support decisions. Monitoring also bridges communication gaps between business and development teams by highlighting key performance indicators (KPIs) and using dashboards to track user interactions. It aids in problem investigation by uncovering patterns and locations of issues, while also helping prioritize testing efforts based on actual user data. Moreover, real-time monitoring and alerts can be configured to quickly address issues, ensuring that critical functionalities operate smoothly. Despite its benefits, many firms lack comprehensive monitoring systems, and the text encourages testers to advocate for their implementation to gain valuable insights and improve product quality.