Always, but I’m a former Googler, so performance was always a huge concern with each and every frontend change we made.

Rendering something to a page without errors should be the starting goal, where you then shift focus to readability, accessibility, maintainability, interoperability - all that other stuff that actually matters more but is opaque to users - but in most cases, it’s the end goal, and all that other stuff isn’t considered at all.

IMO, the web would be a lot better if frontend devs spent more time learning how to use their tools instead of logging everything to the console.