I wasn't talking about optimization! I was talking about non-pessimization, which includes not prematurely abstracting/generalizing your code.

I've seen people making poor decisions at the outset, and having code philosophies that actively make new code 100x slower without any clear gain. Over-generalization, 100 classes and subclasses, everything is an overriden virtual method, dogmatic TDD (luckily, nobody followed that.)

The dogma was to make things more complicated and illegible, 'because SOLID'.