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.
Various Artists: Young Art Sound
Valerie June: The Order of Time
Ibibio Sound Machine: Uyai
Unearthly Trance: Stalking the Ghost
Porcelain Raft: Microclimate
'Get Out' Is a Fantastic Freak-Out
The Feelies: In Between
Call Super: Fabric 92
"Choice in media sometimes doesn't lead to freedom, just paralysis.