R5 — Pair the IKEA effect with completion: only completed configurations produce psychological ownership; abandoned configurators produce frustration, not love

Rule: Design configurator-style tools so that completion is reachable and the completed output is preserved/saveable. The IKEA effect requires completion to fire.

Why: Norton-Mochon-Ariely 2012 (Norton, Mochon & Ariely (2012), Journal of Consumer Psychology — IKEA effect: effort/co-creation raises valuation of the result ("labor leads to love") BUT ONLY WHEN TASK IS SUCCESSFULLY COMPLETED) — building-then-destroying or failing eliminated the effect. Sarstedt et al. 2017 (Sarstedt, Neubert & Barth (2017), Journal of Marketing Behavior — independent conceptual replication of IKEA effect (loom bands); psychological ownership identified as the mediating mechanism) — psychological-ownership mediation. An abandoned configurator produces no ownership boost and may actively frustrate.

How to apply:

• Default completion bias toward "fewer steps" and "save state" support.
• A user who completes a 3-step configuration owns the result. A user who abandons a 12-step configuration owns nothing and remembers the friction.
• For complex builds, support save-and-share (turns the configuration into an owned, named artifact).
• Pair with R2 — Design every multi-step tool for the goal gradient: visible progress + low interaction cost + start-state non-empty when possible — both rules push toward "make finishing easy and visible."