I have read horror stories of feckless fathers mistreating their babies (and worse, I don't want to even think about these stories, they make me physically ill). I also have an acquaintance who has a daughter who has, unfortunately, just become pregnant with her useless boyfriend (who tried to get her on drugs, is violent to her, etc.).
I could not help thinking why it is that the feckless men seem to "breed like rabbits" (for want of a better phrase) - while I also know a guy who is homosexual, who loves children and is kind, hard-working and gentle, yet as he once explained to me, he is "wired up" so that he just cannot reproduce. I suggested adopting to him, because he is great with kids, but he feels strongly that a child should have a male and female parent. He has lived with women in shared flats and says he prefers female company, yet he is like a computer with hardware that has just not been "programmed" like the majority.
This is just one example I know, and there is probably some bigger "reason" in nature why it is so... but it just seems wrong to me and that it should be the other way around!