Zero-Tolerance for Failure

When to Use

• Establish failure-prevention culture and operating norms for mission-critical systems
• Apply HRO principles (preoccupation with failure, reluctance to simplify, sensitivity to operations, commitment to resilience, deference to expertise)
• Design defense-in-depth, fail-safe, and fail-closed controls for software, infra, and OT
• Define verification gates, independent checks, and release hold criteria
• Architect redundancy, isolation, and graceful degradation with explicit failure modes
• Facilitate pre-mortems, FMEA, and risk registers before high-stakes change
• Author stop-the-line policy and escalation when quality or safety signals are ambiguous
• Select and track prevention metrics (defect escape, near-miss, repeat incidents, gate bypass)
• Coach leadership behaviors that counter normalization of deviance and blame theater
• Brief engineering and ops on zero-defect aspiration vs error budgets for the right domain

When NOT to Use

• Own SLI/SLO definitions, error-budget policy, and burn-rate alerting →

  site-reliability-engineer

• Run live incident war room, SEV classification, and status communications →

  incident-management-engineer

• Design backup/immutability, RTO/RPO recovery, and ransomware restore architecture →

  cyber-resilience-engineer

• Enforce CI compile/lint/test gates without broader prevention program →

  build-validator

• Facilitate sprint ceremonies, backlog grooming, or team agile transformation → agile coaching skills
• Issue HR warnings, performance plans, or legal disciplinary guidance → escalate to HR/legal
• Own classified ATO/accreditation packages without operational excellence deliverables →

  classified-cyber-security-senior-manager

  (pair for cleared context)
• Produce ADRs and integration patterns without failure-prevention lens →

  senior-system-architecture

  (pair for architecture)

Related skills

site-reliability-engineer

incident-management-engineer

cyber-resilience-engineer

build-validator

classified-cyber-security-senior-manager

senior-system-architecture

bcm-disaster-recovery-specialist

incident-responder

Core Workflows

1. Scope, limits, and charter

references/zero_tolerance_scope_and_limits.md

2. HRO principles and operating mindset

references/high_reliability_organization_principles.md

3. Prevention, verification, and gates

references/prevention_verification_and_gates.md

4. Redundancy, degradation, and fail-safe design

references/redundancy_degradation_and_fail_safe.md

5. Pre-mortem, FMEA, and risk registers

references/pre_mortem_fmea_and_risk_registers.md

6. Leadership, culture, and metrics

references/leadership_culture_and_metrics.md

Outputs

• Failure-prevention charter — scope, principles, RACI, interfaces with SRE/IR/QA
• Gate catalog — hold points, owners, evidence required, bypass rules and audit trail
• Design review pack — fail-safe/fail-closed decisions, degradation modes, verification plan
• FMEA / pre-mortem record — failure modes, causes, controls, residual risk, owners
• Stop-the-line policy — triggers, authority, duration, comms, and restart criteria
• Metrics dashboard brief — defect escape, near-miss, repeat incidents, gate effectiveness
• Leadership playbook — behaviors, rituals, and anti-patterns (learning vs blame)

Principles

• Prevent over punish — optimize systems and norms; avoid blame theater and hidden workarounds
• Fail closed by default — ambiguous safety or auth states deny; document explicit fail-open exceptions
• Independent verification — separation between build, check, and approve for high-criticality change
• Deference to expertise — elevate domain experts at the boundary; leaders ask, not override silently
• Measure escapes and near-misses — lagging severity alone rewards luck; track what almost failed
• Stop-the-line is a gift — halting bad change is success; normalize escalation without career penalty
• Pair with peers — reliability math (SRE), incidents (IR program), recovery (resilience), builds (CI)