Data and metrics are essential tools to learn from incidents, as they provide you with objective and quantitative information to understand what happened, why it happened, and how to prevent or mitigate it in the future. For example, data and metrics can help you detect and diagnose incidents faster and more accurately by using alerts, dashboards, logs, traces, and other sources of data. Additionally, they can be used to assess and communicate the impact and severity of incidents through key performance indicators (KPIs), service level objectives (SLOs), service level indicators (SLIs), and other metrics. Furthermore, data and metrics can be used to identify and analyze the root cause and the contributing factors of incidents through correlation, causation, hypothesis testing, and other methods of data analysis. Lastly, they can be used to evaluate and prioritize the lessons learned and the action items through cost-benefit analysis, risk assessment, return on investment (ROI), time to detect (TTD), time to acknowledge (TTA), time to resolve (TTR), mean time to recovery (MTTR), and other metrics.