I've always hated the "I never wanted kids but had one and now I couldn't be happier" line, with its implication that you either don't know your own mind, or should have kids even if you think you don't want them because you'll turn out happy anyway. And the same with anyone pressuring you into having children through any means.
I see so many people almost suggesting that you just have kids whether you want them/are ready for them or not, and it'll all turn out great. ("When you have kids, you just know what to do. You just get on with it. You feel this rush of love, and everything is all right").
What if you don't/can't? Most people can provide the basics - feed a kid, clothe a kid, and not abuse it. But nurturing a child, giving yourself to them and providing financially without breaking yourself? That's harder.
Once you have a child, you can't take it back. They'll be fully dependant on you for years to come. And your behaviour over the next 18 years will shape the person they become. I see so many parents who have ended up broken. And children/adults who have been screwed up by their parents. Families who are NC. People who have kids and then can't be arsed with them, or resent them, or just plain fuck off into the sunset leaving them behind.
It's like having children is the default, and you really need to justify not having them. But really, shouldn't it be the other way around? Rather than "have kids, it's great!", wouldn't "think carefully, and have kids if you're sure you're ready. And if you're not ready/don't want to, then that's fine" be better?
And I'm not putting parents down - I have so much respect for most. It takes so much to be a good parent, and not everyone is capable of it, or wants it. And that's fine too.