A recent study by AI research nonprofit METR has found that experienced software developers working with AI coding tools are actually taking longer to complete tasks, contrary to common assumptions. The study, which examined developers using Cursor, a popular AI coding assistant, found that task completion times increased by 19% when AI was used, despite developers’ belief that they had improved efficiency by 20%. The research, published earlier this year, challenged the widespread belief that AI would significantly speed up development workflows. Lead authors Joel Becker and Nate Rush were surprised by the results, as Rush had initially expected a 2x speedup. The findings suggest that while AI may not always boost productivity in familiar codebases, it can still provide value by making the development process more enjoyable and less mentally taxing.