Nobody says you have to. I am proposing an alternate value system that says we don't need to claim these things are always absolutely mutually exclusive. I think it depends on the company, the parent(s), the child, the culture, the legal framework around parenting and work, and a zillion other things. Maybe you live with your extended family and it's understood that a grandparent will take on a lot of the work. Or an uncle. Or maybe your government provides extensive day care and education options. Or maybe you have an office where a child can be present.