Why is the build quality of the Audi A2 superior to other subcompact cars?

I've read that the Audi A2 is of exceptional quality for a subcompact car, but I'm curious as to what specific features or materials contribute to this. Can someone please explain?

The Audi A2 boasts a unique aluminum space frame construction, which provides superior strength and rigidity while remaining lightweight. This design feature allows for better handling and safety.

Having owned multiple subcompact cars, I can confidently say that the Audi A2 stands out in terms of material quality. The interior is upscale and well-crafted, with attention to every detail.