It's not that Berg does not have a good voice (she has a strong, sweet one), or because she is not physically attractive (she is), but her versions of her own songs are more subtle than the commercial ones by bigger name artists.
David Bowie: Who Can I Be Now? (1974/1976)
Erroll Garner: Ready Take One
Ways of Seeing Kate Bush
Play Out the Play: Orson Welles’ Chimes at Midnight
Hieroglyphic Being: The Disco's of Imhotep
On Friedrich Nietzsche's Early Intellectual, Emotional, and Spiritual Development
The Frightnrs: Nothing More to Say
"Rainer Werner Fassbinder is the whole show.