Monitoring Past Performance vs. Alerting Real-Time Issues: What React Teams Are Missing

The Real Problem: The Gap Between Past Data and Present Issues You're running a React app in production. You have monitoring tools in place. You check the dashboard regularly. And yet. Tuesday morning, you deploy. Everything looks good in staging. Users are happy. By Thursday, things have changed. Your app's Largest Contentful Paint (LCP) jumps from 1.2s to 2.8s. But you didn't notice. Your users did. By Friday, your app store reviews are filled with complaints: "This app is so slow." It's too late now. At this point, your monitoring tool tells you: "Yes, looking at the past hour's data, LCP has indeed increased." But that's just reporting after the fact. "Monitoring" and "Alerting" Are Two Different Things—And Your Tools Are Missing One You probably already have some form of monitoring in place: Error tracking tools (capturing exceptions and stack traces) Analytics platforms (showing you performance data from the past week) APM solutions (analyzing past traces) What all of these have