Co-Creation or Co-Destruction — Redesign Foyer Connecté's Service Journey

A four-round, advanced service-design simulation set inside Foyer Connecté SAS, a Lille-based connected-home energy service with 240,000 subscribers (€51.8M annual revenue, 34% contribution margin) hit by the 'Cold-Snap Backlash' of March 2026. A February cold snap pushed bills up despite the savings promise; monthly churn jumped from 1.8% to 3.4%, putting ~33,600 subscribers and ~€7.3M of revenue at risk, and the press ran 'L'appli qui ne fait pas d'économies'. The twist: this savings service is not manufactured and shipped — it is co-created in interaction. Value only materialises when customers integrate their own resources (honest schedules, occupancy data, acting on coaching nudges); when the interaction fails, value is actively co-destroyed (Plé & Cáceres). Diagnostics show 62% of complainers never finished onboarding and 28% rated coaching 'preachy', and a ~4,000-strong cluster is gaming the savings guarantee for €22 credits (€88,000 and rising). Playing the service-redesign team under a hard €2.0M service-ops cap and a 30% margin floor, you (1) map the customer journey and locate the two touchpoints where value is co-destroyed, naming whose resources failed — the firm's, the customer's, or the integration; (2) redesign the journey by choosing resource-integration touchpoints against the cap — a guided onboarding wizard, an honest 'comfort vs savings' expectation reset, usage-driven coaching personalisation, and a peer community — while protecting margin; (3) author the co-creation rule (firm contribution, customer contribution, failure handling) and contain the misuse cluster by enforcing, designing out, or converting the gamers; and (4) sequence a 60-day recovery plan against a second cold snap arriving in 45 days, easing onboarding friction without re-opening the co-destruction gap. The math rewards subtraction over feature-piling, designed-out risk over blanket enforcement, light-touch integration over heavy friction, and respecting the cost cap — and punishes the five classic errors: adding instead of redesigning, misdiagnosing churn as a marketing problem, punishing all 240,000 for the 4,000, friction as a cure, and ignoring the cap or the clock. Final KPIs track Co-Created Value, Co-Destruction risk, Customer Satisfaction, and Service-Ops Cost against the €2.0M cap.