At the lack of knowledge people have. And maybe its not the lack of knowledge but they just don't care and will do whatever they want anyways. I am just constantly amazed at how many people don't breastfeed and I really am in the minority. A friend of mine just had her first baby and was asking when she could feed him baby food/ cereal. The first three responses were 3 months! And one person told her to put it in his bottle. She breastfeed for 3 days. I don't know her story but your milk doesn't even come till day 3 or later.
I think back to when I had my first and there were a lot of things I didn't know that I wish I did. I was the first of my friends to have a baby. but there was a lot I questioned and researched on my own too. I also wasn't on this site yet. Learned so much from Cafemom.