Why does the Audi A5 have a sportback design?

I'm wondering what the reasoning behind the sportback design is and if it has any impact on performance or functionality. Does it create more interior space or improve aerodynamics?

The sportback design in the Audi A5 combines the sleekness of a coupe with the practicality of a sedan, creating a distinct and versatile vehicle. It also allows for easier access to the rear seats and provides additional cargo space.