Yeah i think it was a combination of neglect of the animal in general, low social interaction, lack of any stimulus (toys enjoyment) and the taunting of the children gave the German Shepherd a considerably negative view of not only hoomans but life in general.

The doggie was starved for connection, interaction, basic decency and love. being devoid of such fundamental principals can have a devistating impact on mankind as is outlined by maslow's hierarchy of needs, i also believe a similar concept can be applicable (although differing in some ways) when applied to the various life forms on the planet. if we are to keep animals as pets it is our responsibility and duty to care for their needs.