Why do people fuss over a nursery?

I really don’t understand. Does your baby not stay in your bedroom for the first 9-12 months of his/her life? Are you not anxious having baby sleep in a completely different room? Both of my babies have been in our bedroom for the first 9-12 months and so will baby 3, it reduces risk of sids too. Each to their own but I could never personally do it 😕 maybe its just different in America?