What's the point of having kids?

I don't understand how people have kids even though they know they will suffer. There is a saying that no one wants to see their loved ones suffer. If that's true, then why do people have kids and make them suffer for their own selfish reasons? What if their kids die in the most painful ways-getting raped, dying in a horrific road accident, or taking their own lives? How can people be so selfish to bring children into this wicked world? It's my opinion about life.