If you are a startup (many HN readers are), employee hours are relatively expensive. The goal is to get a product out as fast as possible, and most of the time you fail at making a working product anyways. Meanwhile, you only have to spend money on servers once you have a successful product. Deferring the problem makes sense here.
On the other hand, I personally write code that'll be near guaranteed to run millions of times in some factory somewhere, and there's little benefit if I ship my code before the factory starts making stuff. I'll take the time to write high-performance and high-quality software because there's now a financial benefit to doing so.
But ultimately, it's my boss who gives me insight into what I should be doing. Not a book, because the book doesn't have context that [company] will lose tens of thousands of dollars every day that I don't fix [issue].