Because it has the regulatory requirements I detailed in my post for housing developers.
> The UK is well known for unaffordable, poor-quality housing
And houses in the states aren't poor quality? Do builders over there even know what bricks are?
Freeholds in some areas have a reputation for being unaffordable, sure. I'm not so sure that the shared ownership and affordable rent properties I refer to have this reputation, but it is clear that there's not nearly enough housing stock for demand.
Quality is definitely variable across all housing stock, but I'm not sure I'd say all new builds are of a poor quality.