You can't have a current flow without a potential, so where there is current there will be potential and vice versa as defined by ohms law. When the human body becomes a good path then there is potential for harm. There are many factors that contribute to electrical hazards. Current flow is only one factor and current flow cannot occur without a circuit path, a load and a source. When well designed,operated, maintained & respected electric systems work well. When systems fail usually, more that one factor is at fault.