Redraw Week 2 picture in one sheet. When 3am alert arrives, what to check in what order? Bill suddenly $10,000 higher, where to start digging? "Some users slow," which query to run? Every CloudWatch tool ultimately answers these three questions.
If Week 2 is "data collection," Week 3 is "alerting and visualization," then Week 4+ automation/DR/cost management builds on top. As review week, today's focus: not re-explain concepts, but why designed this way and how broken in practice, bundled by case study, standard, and theory for depth.
CloudWatch started 2009 as simple metric service showing EC2 CPU, network, disk I/O