The AI Coding Productivity Illusion

Developers are convinced that AI coding assistants make them faster. The data tells a different story entirely. In one of the most striking findings to emerge from software engineering research in 2025, experienced programmers using frontier AI tools actually took 19 per cent longer to complete tasks than those working without assistance. Yet those same developers believed the AI had accelerated their work by 20 per cent. This perception gap represents more than a curious psychological phenomenon. It reveals a fundamental disconnect between how developers experience AI-assisted coding and what actually happens to productivity, code quality, and long-term maintenance costs. The implications extend far beyond individual programmers to reshape how organisations measure software development performance and how teams should structure their workflows. The Landmark Study That Challenged Everything The research that exposed this discrepancy came from METR, an AI safety organisation that conduc