In the real world there is no entirely reasonable code base. There's always going to be some aspects of it that are kind of shit, because you intended to do X but then had to change to doing Y, and you have not had time or sufficient reason to properly rewrite everything to reflect that.
We tend to underestimate how long things will take, precisely because when we imagine someone doing them we think of the ideal case, where everything is reasonable and goes well. Which is pretty much guaranteed to not be the case whenever you do anything complex.
Aluminium smelting is so energy intensive that Iceland, a country with a population of less than 400 000, is the world's 12th largest producer of it, even though the raw materials aren't mined there. Iceland just has cheap geothermal and hydroelectric power.