Design Arena study: Model choice accounts for only 3% of website appearance—randomness dominates

Design Arena, the AI benchmarking platform, measured 64,537 AI-generated websites across 164 models and found that model selection has minimal impact on final design outcomes. The study reveals an unexpected distribution: AI model choice accounts for approximately 3% of how a website looks, while prompt engineering influences about one-sixth (16.7%). The remaining four-fifths—roughly 80% of the variance—stems from what Design Arena describes as "the luck of a single try," highlighting the inherent randomness in generative design outputs.