Why Does Lufthansa Still Fly The Airbus A340?

In the competitive world of aviation, airlines are constantly after newer and more fuel-efficient aircraft to keep their costs low. This is primarily why the first of the aircraft types to be grounded and retired by airlines around the world during the COVID-19 pandemic happened to be quadjets, because utilizing aircraft with four engines guzzling fuel was not economical and inefficient compared to newer aircraft on the market.