Ask HN: What Is a "Living Standard"?

Came across this: [https://whatwg.org/principles] that speaks of a technical standard being "living". It is explained as ""Living Standard" means a single, unified technical specification, published by the WHATWG as a Living Standard." Which makes little sense, i.e. using the term to define itself. Someone also called JSON a living standard. What is this philosophy? All web searches seem futile as they point to "standards of living" related material. So, what makes a standard "living standard"?