Decision Goal: User signup approval system. Input Variables: - email validity - password strength - user verification - blacklist status Conditions: - valid email - strong password - verified identity Decision Rules: If all valid → approve If any critical fail → reject If uncertain → review Decision Tree: Start → check email → check password → verify user → decision Execution Outcomes: - approve account - reject signup - send for manual review Fallback Logic: If verification fails, trigger re-verification. Optimization Suggestions: Group validation checks into a single reusable module.