We use the solution to monitor and investigate issues with production services at work. We're periodically reviewing the service catalog view for the various applications and I use it to identify any anomalies with service metrics, any changes in user behavior evident via API calls, and/or spikes in errors.
We use monitors to trigger alerts for on-call engineers to act upon. The monitors have set thresholds for request latency, error rates, and throughput.
We also use automated rules to block bad actors based on request volume or patterns.