The one on the left isn't awful (like the one on the right is) but she looks like she's been living on the street a few months, poking herself with dirty needles.
Rush Limbaugh said it best, speaking of Chrissie Hynde of the Pretenders...Looking at the one on the left, I think this fits:
"She looks like someone who could give a man 6 or 8 different sexually transmittable diseases...but you wouldn't care."
As for the other one, I wouldn't characterize her as ugly, but to say she's "plain" would hurt her just as bad.