Clearly the value of business being sold is not dependent on the application of standardized programming approaches to quality. I mean, who would even think it

Clearly the value of business being sold is not dependent on the application of standardized programming approaches to quality. I mean, who would even think it is? There are also alternative approaches to achieving quality, and there was that report/"study" circulating around that claimed Team Software Process actually beats most agile/extreme programming methodologies in at least one metric (or two: defect rate and time to completion, IIRC). Of course, none of the actual "agile" development teams do clear-cut TDD or Extreme Programming either, so you are never comparing apples-to-apples. As a corollary, I'd also say that neither does the UI or UX matter that much to success, and there are simply a bunch of intangibles that can make or break a product. But one "tangible" thing is that you've got to be serving some customers' needs, and need to continue to do that. And rare are businesses which have a need of "my button needs to be rounded and 10px away from the next button" or "my code needs to be unit tested": those are actually "my customer can get their work done through my product" and "it should rarely break". None of this means that you should not invest in pretty/functional UI/UX or well-tested code. Just don't expect that to mean much in the grand scheme of things. They will affect your ability to hire top-level people once you are an established business, though. (I personally am too attached to "high-quality" [as in well tested] code and would struggle to kick off a start-up for that reason only, even though ideas keep popping up :)