I suspect a lot of people are attracted to the idea of “build, measure, learn” because it implies consent. We’ll try some things out that we think may work but we don’t know will work, see what happens and update our opinions. It’s the “yes, and” of product development.

The reason this is attractive is that a lot of designers and product people find themselves at companies which require certainty/proof before agreeing to go ahead. It can be very tiering if you’re constantly having to justify your own existence/expertise. Very “no, but”

It’s also pretty much impossible to guarantee something will work in advance. So if you work in a culture like this you spend most of your time trying to start projects, and get very little done as a result.