I think it's not having enough money to meet current lifestyle expectations. It's technically possible to raise a family of nine in a two-bedroom dwelling with

I think it's not having enough money to meet current lifestyle expectations. It's technically possible to raise a family of nine in a two-bedroom dwelling with three beds, and one of my great-grandparents grew up in such a household, but to live like that today would be considered child abuse. People prefer to view this as a lack of money due to increasing cost of living or stagnant wages because those are more comfortable to talk about, but an increasing standard of living raises the awkward question of whether it's even a good thing to have more (or any) kids.