I am always baffled by women that have children with men that are proven to be rubbish fathers.
Most of the time it's because they've only had his side of the story.
"My ex was a right lazy cow, I was at work all day grafting 8am til 7pm and she expected me to start doing housework when I got home..."
"My ex is a right psycho, wouldn't ever let me help me with the kids so then when we split up they wouldn't come visit with me because they weren't used to being alone with me..."
"My ex is a right bitch, I love those kids and she stops me from seeing them..."
"My ex is a right greedy witch, all she's bothered about is maintenance..."
And alongside all of this Jackanory-for-Dickheads the new girlfriend is fed lines like:
"I was lost until I found you..."
"She left me so broken and you've healed me..."
"I'm happier with you than I ever was with her..."
So the new girlfriend goes on believing that the ex was the problem, the useless man was the wronged party, and that she brings out the best in him. He of course will be on best behaviour until he has his feet well and truly lodged under the table then the cycle of uselessness will begin again.
A lesson I have learned in my 40 years - you can learn a hell of a lot about a man in how he speaks about his ex partners. One "psycho"? Meh, it happens. Several "psychos"? Almost certain that the problem isn't the women. And if the "psycho ex" is the mother of his child(ren)? It either means he was/is a dickhead and you should run or you'll be dealing with his shit for years, or she actually is an awful person in which case you should also run because if they have a child you will be dealing with her shit for years to come.