I am an older parent myself, swearing I would never have kids for most of my life. Then I hit my mid 30s and all of a sudden I met a girl who I didn't think was a total whore for the first time in my life and decided to have kids. Over time she evolved into a pain, but the kids are great. Very well behaved and excelling in school. Well rounded. I started them training at 6 years old. The joy in it all is putting time into them so they can avoid all the b.s. I went through. My parents were very successful professionals but gave very little time to me and my 2 brothers. We were raised by nannies, and my mom still brags that she has never changed one diaper in her lifetime.
Who knows what the future brings. Having a sick child or one that has developmental problems can cripple your life no doubt. In my case, having kids and guiding them meant giving them a chance to have a great fun life. Hopefully they do. Even a guy with everything like Arnold had 5 kids. Hard to explain that sudden urge.
That's what I said: most are only worried abvout THEIR own dilemmas in life. What about kids? Are you sure you are giving them the best genes/upbringing/future? Your kids doesn't give a fuck about the shortcomings of your childhood, it's you that is solving these using your kids (so this time it will be different).
People are egoistical assholes (it's always about "me me me me. I felt, I realised, I decided, I came up toa decision, etc..". Even the ugliest motherfuckers find a rationalization for it, while in truth they are making a crime against these offsprings) and many shouldn't ever have kids, but many somewhy think that they are the perfect candidates to have them. Oh sweet irony..