I am a charity shop manager looking to appoint a new volunteer. It looks like it may come down to a choice between two young women. Girl A seems reliable and nice enough, and would be probably be ok. Girl B seems to have the gift of the gab, is a cool dresser and have a feeling would be popular with the regular customers, but in theory might be less reliable on occasion than the other.
My head says Girl A to be on the safe side, but I might choose Girl B on the basis she'd be more fun to work with. I also think Girl A will find another (maybe better) voluntary role very soon anyway, maybe quicker than Girl B.
YABU for Girl A
YANBU for Girl B