When I design a toaster oven, I don’t design one part that tries to get electricity to the coils and a second part that tries to prevent electricity from getting to the coils. It would be a waste of effort. Who designed the ecosystem, with its predators and prey, viruses and bacteria? Even the cactus plant, which you might think well-designed to provide water fruit to desert animals, is covered with inconvenient spines.
Well, to be fair, if I want to design an image classifier, I might very well make one part that tries hard to categorize photos and another part that tries hard to miscategorize them.