***The reasons are complex, but the educational system must take a lot of the blame along with...***
Actually, while I agree with you, there's one reason that's very simple. When a young man wanted sex, he was expected to get married and to be able to support a family. That was a strong incentive for him to get a job and work hard.
When women's lib told the women to give it away for free, the incentive disappeared.
I have a feeling that is the the biggest factor. Why do us men go out and become a doctor? So we can get more 'chicks'. Why do we go to the gym? So we can get more 'chicks'.. How many men honestly work out so that they are healthier?
I'd have to disagree. I know my fair share of lazy dads. Good work ethic isn't an outcome of marriage alone, it is something that an individual develops over time through environment and family. When I was single, I worked my butt off - despite my fair share of "girlfriends".