I'd even go a step beyond "customer feedback". I insist upon "deep immersion" in the customer's business.

My favorite analogy for software development is ham and eggs. The chicken was "involved", but the pig is "immersed" in the process. Hate to say it this way, but you gotta be the pig.

From one point of view, an ecosystem is the opposite of a vacuum. And yes, you should develop software in one of those.

A singularity is the opposite of a vacuum. Lots of metaphor fodder there.