I don't know everything there is to know about how a car is built, but I'm not going to assume that dwarves carve their way through the floor of the factories to finish up the parts I'm unaware of.
I see the parallels you are trying to make, but I think the human body is orders of magnitude more complex than a car, and its still possible that we don't know everything about how electricity functions inside us - how it influences our development from a single cell jumping through millions of years of evolution.
