{
  "schemaVersion": 1,
  "type": "principle",
  "id": "pareto-principle",
  "evaluation": {
    "reviewedOn": "2026-10-19",
    "status": "limited",
    "modes": [
      "application-fixture"
    ],
    "summary": "The illustrative priority list kept a critical access failure with one report above more frequent low-severity issues. It made no 80/20 estimate from synthetic counts.",
    "reportUrl": "/design-evaluations/principle-pareto-principle.json",
    "identity": {
      "target": "Original IonBin synthetic interface example; no external product or human-participant study.",
      "version": "2026-10-19 local fixture",
      "integrity": "SHA-256 f85d1056afd667225a1e0364edfb8f25b4693ffa7b2b8c7d7af5b92338b85ee4 identifies the exact HTML fixture only."
    },
    "environment": [
      "155.0.8059.82 Chromium; fresh context with all network requests blocked.",
      "Synthetic inputs, memory-only state, reduced-motion preference, 1280px and 320px viewports."
    ],
    "tests": [
      {
        "name": "Severity before frequency",
        "mode": "application-fixture",
        "method": "Exercise the original local application fixture and inspect the resulting controls or DOM state.",
        "result": "pass",
        "observation": "The illustrative priority list keeps a one-report access failure above frequent low-severity issues; it makes no 80/20 estimate."
      }
    ],
    "security": {
      "scope": "Review of the local example’s stated interaction boundaries; no backend, authentication, production permissions or external service was exercised.",
      "findings": [
        {
          "level": "caution",
          "basis": "advice",
          "title": "Low frequency can still carry high harm",
          "detail": "Security, privacy and accessibility failures cannot be dismissed because they are rare in a usage log. Sampling and reporting barriers can hide affected users."
        }
      ],
      "limits": [
        "The example has no real authorization or persistence layer; its UI behavior cannot establish the security of a deployed workflow."
      ]
    },
    "practicalCaveats": [
      "Use measured frequency together with severity and coverage; preserve recovery and privacy paths even when used infrequently."
    ],
    "limits": [
      "This checks an authored application example, not the truth, effect size or generality of the named principle.",
      "No users, assistive-technology participants, physical devices or production task outcomes were evaluated."
    ],
    "sources": [
      {
        "label": "ASQ: What Is a Pareto Chart?",
        "url": "https://asq.org/quality-resources/pareto",
        "scope": "Quality-method guidance for measured frequency or cost and cumulative contribution."
      },
      {
        "label": "Juran: The Non-Pareto Principle, Mea Culpa (1974)",
        "url": "https://www.juran.com/wp-content/uploads/2021/03/The-Non-Pareto-Principle-1974.pdf",
        "scope": "Original author's account of the principle's naming and development; its universal rhetoric is not adopted as a UI fact."
      }
    ]
  }
}