These are often badly built homes too as they're mass built only for the purpose of selling them. Everything is built down to a cost and "features" are added only to raise the value, not to actually be useful, such as making garages super tiny or even inaccessible, or adding cosmetic features like extra complex roofs that cause issues down the road.
I can't imagine buying a new house where I can't be involved in the entire construction process. I would want to be able to visit it every day to oversee the work, and give feedback and requests as I see things. But they don't even let you do that, as they technically own the house until it's built.
Cities will often give you trouble if you want to build your own house too, and in some cases may not even let you. If you go that route, even if you hire some trades, then you have more say in what's going on though as you're basically the foreman.