Why did Mozart write a little night music?

There's no record or documented reason stating why Wolfgang Amadeus Mozart wrote Serenade No. 13 in G major, popularly known as ''A Little Night Music'', though, most likely, it was composed for a social event, possibly as background music, to entertain guests at dinner or during social parties held during the evening, which explains ''Night'' within the title. It remains as one of Mozart's famous musical compositions of its kind. Some also regard it as ''Mozart's Serenata Notturna''.