AP-005 — Customer driven

Every product decision, technical trade-off, and design choice is evaluated through the lens of customer value. Technology exists to serve customers, not the other way around.

Customer experience metrics are first-class engineering metrics. Onboarding completion rate, self-service rate, time-to-interactive sit alongside latency and availability — not in a separate product report. NFRs that directly affect customers are hard constraints. Technical debt that degrades the customer experience is prioritised above technical debt that does not.

The customer test: Does this make things simpler or harder for the customer? A technically elegant solution that produces a confusing experience is not acceptable.

Relationship to other principles

Principle	Relationship
AP-001 KISS	Simplicity in design usually produces a simpler customer experience — the principles align.
AP-003 Compliance by design	Automated compliance controls (GATE mode) protect the customer while keeping the experience smooth.
AP-008 Real time where it matters	Real-time capability earns its place partly through customer experience — authorisation latency is a customer metric.
AP-009 Robust and serviceable	Operational reliability is a customer experience metric — downtime and slow recovery directly hurt customers.

See the full architectural principles index.