German Shepherd Dog Problem?

Okay my dog is 10 weeks old and GSD Czech blood line. I am new with dogs... I know it was a mistake but I already have him and bonded with him. question 1: why are the czech bloodlines so diff. from the others? When I train him he always does good but only when he sees a treat in my hand. If i have no treat he does nothing. Also, why are GSDs only for experienced dog owners? I have had him for a while and he is doing amazingly good. Not a handful at all.