User blog comment:WarrenWitch/Yang nails it, Pyrrha gets her man, Weiss chooses the lesser of two evils...and Ruby hits a crow/@comment-11942246-20130816050909/@comment-10390252-20130816135729

And there is your key wrong assumption: Signal isn't a 'Monster Slaying School'. Beacon is the Monster Slaying School. All the graduates from Signal and other feeder schools would have is the basic combat drill and maintenance skills. You learn about the monsters and how to kill them at Beacon, not before.