

I mean, putting in a bit of thinking before you actually hit the keyboard can be an incredibly effective form of optimization, if you can get for example an O(n^2) down to an O(log n). You’ll even save time on not having to rework the thing later, and if you build on poor foundations, chances are you’ll stumble upon fundamental architectural challenges down the road, which can be extremely costly in terms of development time.
More space isn’t necessarily a better thing, there are very real diminishing returns after a certain point. Plus, living space is both an asset and a liability - you have to pay to keep the space warm or cool depending on your local climate, and you also have to clean the space.