The German Shepherd is essentially a trotting dog.  Developed for herding the dog would work all day - almost always in a trot never tiring.  Therefore strict adherance to the structural makeup is of utmost importance.  Croup fomation and shoulder angulation are just many of the features that serious dedicated breeders work for in their breeding stock.

With sound structural efficiencies for long, arduous work, the standard for the German Shepherd Dog calls for mental stability and a willingness to work. The dog should be approachable, quietly standing its ground, showing confidence and a willingness to meet overtures without itself necessarily making them. It should be generally calm, but eager and alert when the situation warrants. It should be fearless, but also good with children.

The German Shepherd Dog should not be timid or react nervously to unusual sounds or sights. A dog that is overly aggressive because of its overall fears of people and events can be extremely dangerous.  These dogs should be eliminated from the gene pool as dogs that are not structurally sound.