Pattern: AI Productivity Paradox Quantified — Three Independent Studies Converge on Net-Negative Signal

paddo.dev·high signal

Three independent research efforts now converge on the same conclusion: AI coding tools increase perceived productivity while potentially decreasing actual output quality. METR (July 2025): developers 19% slower but believe they're 20% faster. Lightrun (2026): 43% of AI code fails in production post-QA. Fastly (2025): only senior developers (2.5x more AI code shipped than juniors) achieve measurable speed gains, despite juniors using AI 37% more. DORA's counterpoint shows +21% tasks completed but flat organizational delivery and decreased stability. The pattern: AI amplifies existing skill, it doesn't replace it.