[Current] Why does the current in the circuit actually pass through all electrical appliances at the same time?

The essence of current is the directional motion of charged particles ... In fact, the speed of current is very slow ... Then why does current pass at the same time? Here, for example, the Three Gorges Reservoir is the power source and the Yangtze River is the power line, so when the Three Gorges releases water (when the battery is powered), the water in the Yangtze River adjacent to the Three Gorges will be pushed by the water in the Three Gorges immediately … and the water far away from the Yangtze River and the water in the lower reaches of the Yangtze River will be pushed at the same time … that is to say, the water flows all over the Yangtze River at the same time … so the water flow is the same.