There is also a charming story (strangely under new/jazz) about why Mozart started composing fuges:
Wrote Mozart regard to his Fugue K394b :
[...] This fugue has been created expressly for my own Constance. For she will listen to nothing except fugues, particularly fugues by Händel and Bach, and upon hearing me play them, often by heart, she would ask me whether I had never written one; when I answered no, she would reproach me for not wishing to compose the most artistic and the loveliest thing that music had to offer, and never stopped asking me to compose one for her. [...] In time and if the right opportunity arises, I shall write five more and give them to Baron van Sviten [sic!], whom I know to possess a veritable treasure of good music.
