Two numbers from the 2026 Q2 State of AI Impact report have raised a lot of questions for me about the impact of AI on “quality”.

Across a sample of more than 500 companies, code maintainability improved 3.8% between Q1 and Q2. Over the same period change confidence fell 6.1%. Maintainability asks how easy the codebase is to understand and modify. Change confidence asks whether developers trust that their changes won’t break things.

Those two measures have historically moved together. Code you understand is code you feel safe changing. Now they are moving in opposite directions.