Way too often that is used as an excuse for various forms of laziness; to not think about the things you can already know. And that lack of thinking repeats in an endless cycle when, after your trial and error, you don't use what you learned because "let's look forward not backward", "let's fail fast and often" and similar platitudes.
Catchy slogans and heartfelt desires are great but you gotta put the brains in it too.
A lot of people are so enamored by speed, they are not even taking the time to carefully consider the full picture of what they are building. Take the HN frontpage story on OpenCode: IIRC, a maintainer admitted they keep adding many shallow features that are brittle.
Speed cannot replace product vision and discipline.
Discovery is great and all but if what you discover is that you didn't aim well to begin with that's not all that useful.