Though I enjoy the films in this series, the whole concept is just so silly! Someone dies a horrible violent death...so they in turn become a horribly violent spirit who kills indiscriminately? Why attack people who never did them wrong? And the victims all end up dying of horrible violence, so wouldn't THEY then become "Grudges" of their own? Wouldn't the world already be filled with these spirits? It's not like we all die in our sleep! There's just no logic.