Last day: synthesize all 16 weeks into one decision-making engine. Exam is fundamentally: (1) Read scenario (time constraint, business goal, data volume), (2) Identify pillar weight (Security > all for regulated, Cost for startup, Reliability for SaaS), (3) Find hidden constraint (data sovereignty, compliance, performance SLA), (4) Eliminate decoys (shiny service, overkill, underestimate), (5) Select best trade-off (not perfect, but right for context).