The 8 software engineering metrics AI broke
Summary
AI-coding tools have fundamentally disrupted traditional software engineering metrics, rendering eight common measures unreliable. Metrics like deployment frequency, lead time for changes (cycle time), change failure rate, engineer satisfaction, activity (commits, PR volume), efficiency and flow, lines of code, and Developer Experience (DevEx/DXI) frameworks are now inflated or misleading. This is because AI makes "effort" nearly free, severing the historical link between human effort and output. For instance, deployment frequency now signals tool adoption, not engineering maturity, and artificially short cycle times mask human review bottlenecks. Goodhart's Law, where a measure becomes a target and ceases to be a good measure, is now an unavoidable side effect of AI tool use. The article identifies three metrics that remain robust: Time to recover (MTTR), business and customer outcome metrics, and escaped defect rate, all of which measure results rather than activity.
Key takeaway
For Directors of AI/ML or Engineering Leaders evaluating team performance, you must urgently re-evaluate your software engineering metrics. Traditional activity-based measures like deployment frequency or cycle time are now misleading due to AI's impact on effort. Shift your focus to outcome-based metrics such as Time to Recover, business impact, and escaped defect rate to accurately assess value and quality. This change is critical to avoid making decisions based on inflated or false productivity signals from AI-generated output.
Key insights
AI-coding tools decouple engineering effort from output, rendering traditional activity-based metrics unreliable and making Goodhart's Law unavoidable.
Principles
- Metrics measuring effort or activity are now misleading.
- Goodhart's Law is an inherent side effect of AI tool use.
- Outcome-based metrics are essential for true value assessment.
Method
The article proposes a method for designing new metrics: gather requirements (including AI-era questions), consult management, talk to engineering, pair metrics with guardrails, and deprioritize outdated metrics.
In practice
- Prioritize Time to Recover (MTTR) for reliability.
- Focus on business and customer outcome metrics.
- Monitor escaped defect rate as a quality signal.
Topics
- Software Engineering Metrics
- AI-Coding Tools
- DORA Metrics
- Goodhart's Law
- Outcome-Based Metrics
- Developer Experience
Best for: CTO, VP of Engineering/Data, Executive, Software Engineer, Director of AI/ML, Consultant
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Editorial summary, takeaway, and curation by AIssential. Original article published by LeadDev.