Why does the Audi A6 have a mild hybrid system?

I am interested in the technical specifics of why Audi has chosen to equip their A6 model with a mild hybrid system. I have heard conflicting opinions on the advantages and disadvantages of this technology and I am curious to know the rationale behind its implementation.

The main reason for installing a mild hybrid system in the Audi A6 is to improve fuel efficiency. When the car decelerates, the system captures kinetic energy that would otherwise be lost as heat energy in traditional vehicles. This energy is stored in a battery and can later be used to assist the car's engine during acceleration. This not only reduces fuel consumption but also reduces emissions.