Comprehensive and Detailed Explanation From Exact Extract:

Traditional monitoring works well when systems are static and predictable. However, cloud-native, distributed, and microservice-based architectures create highly dynamic environments. In these cases, observability becomes more effective because it provides visibility across entire systems, rather than focusing on individual components.

From Google’s Observability guidance:

“Traditional monitoring relies on predefined dashboards and known failure modes. In modern cloud systems, component-level monitoring becomes insufficient because failures occur in ways that cannot always be predicted.”

Further, in the SRE Workbook:

“Monitoring individual components does not provide adequate visibility into complex distributed systems. Observability enables teams to understand system-wide behavior and user impact.”

Why options are incorrect:

A Observability is not inherently cheaper.

C While true, it is not the best reason; observability's benefit is broader than scale alone.

D Traditional monitoring can support containers but often becomes noisy and ineffective.

Thus, the best answer is B.