I never heard the term "evolutionary design", although this is apparently the way I design software (and try to teach others to do it). Here's a perfect, short and to the point, explanation of the concept by @CodingItWrong: https://codingitwrong.com/2024/01/29/brief-summary-of-evolutionary-design
Also a good reminder of what the word "refactoring" actually means, despite it being widely used to refer to any arbitrary reshuffling of code.