It doesn’t matter if you take it as a satisfactory answer or not. It’s simply the truth, whether you believe it or not. Plus, it’s backed by mountains of evidence and years of research. There is no need of a deity to explain any of it.
I have no idea what you’re trying to say with the car analogy, and it’s in no way an analogue to what I’m saying.
Let me be clear:
We are the product of millions of years of evolution. The drive to take care of our off springs, whether human or not, is the result of that. There is no deity involved in it. It’s in our nature.
Second, to your point: If some deity is involved in pouring love into mothers to take care of her child, why doesn’t this deity do it for all mothers? Why doesn’t the deity do it for everyone? Why does this deity pick and choose? Does this deity hate poor babies?