One of the problems is that men simply don't want to be husbands? Yes, having enough money to support a family is a big part of it. Many men feel they can't support a family so they decide they don't want to be a husband.
As a woman who is a mother who got pregnant as a teen, I can say that it was never my "master plan" to end up that way. The man I was involved with told me he DID want to marry me but then he changed his mind.
When I finally did marry, another man who said he WANTED to be married. He also later changed his mind and we got divorced.
My current boyfriend now says he never wants to marry. Atleast he's honest about it.
I don't think you should put down mothers in this circumstance. It just goes to show that they don't know the situation they are putting themselves in, how difficult it is. I know I didn't. And for the other people who will look down on you and make you feel like a bad parent/second class citizen. I wasn't even poor. I'm college educated, but still I got the dirty looks. The truly immature and selfish are those fathers who never bother to stick around, help out at all and just bail out on their responsibilities. Atleast the mother is staying around, however difficult it may be. Isn't a mother better than having no mother even if she's young and poor. Don't kick a dog while it's down. It's hard enough for a young single mom. The father can move on with his life without anyone ever knowing he's a young father/abandoned his child and avoid the dirty looks/judgement. But the mom who sticks around and tries, the one who actually loves their kid and is trying to do the right things bears most of the grunt for it. That's not right.