Code Volume vs. QA Capacity

Code volume vs. QA capacity, 2022–2026

Developer output has surged with AI assistance. Testing capacity has not kept pace.

Lines of code per dev / month

+76%

Output growth, mid-size teams

+89%

Incidents per pull request

+23.5%

Change failure rate increase

+30%

Developer output (indexed)

QA test coverage capacity (indexed)

The quality gap

Sources: Greptile State of AI Coding 2025; The Register / Cortex report; MIT Technology Review. Index base = 100 at Jan 2022.