To me, the single biggest distinction between working in a startup versus a traditional organization is that all your work has immediate impact. There are point

To me, the single biggest distinction between working in a startup versus a traditional organization is that all your work has immediate impact. There are points in the lifetime of a startup where code quality and test coverage have immediate impact, and other points where they don't. In a startup you have to learn how to budget your time and effort to create the most immediate impact to further the mission, so if code quality/testing aligns with that then it makes sense to spend time and effort to do it. I've worked at a few startups and I'll give you some examples where it matters and where it doesn't. I was hired as employee #4 at a stealth startup that would turn into a zombie and I was the last non-founder to leave when our runway ran out. At no point in my time there did code quality or test coverage matter even a little bit - our biggest problem was convincing people to pay us, which was particularly difficult because our value to the people we wanted to pay us was intangible (at least to them). This was why the startup failed, we tried to sell to the wrong people for too long (ie, misaligned our values with what our target market actually valued). Code quality didn't matter because we essentially strung up demo after demo in different contexts, the core technology was basically finished within a few months of founding, and the rest of us worked to put it into different contexts to show people what they could do with it. Those demos would never reach production, and most of them had a single developer. Who cares if there were no tests or it was all spaghetti? We were just trying to show off. I'm currently an early employee at another startup and spent a lot of time over the last six months developing ci/cd infrastructure and we're going to make a major push for testing/benchmarking coverage in the next month or so. The reason is that we have a tangible and immediate impact to our business because it directly affects our value proposition. So to answer your question, the answer is it depends. It all matters when it affects the bottom line, because code quality/testing doesn't make you money; it just costs you less money in the future. There is a very definite stage in the life of a startup where that matters, and as a developer in the org you have to budget your time to commit to it when it matters.