Why does a water hose recoil when the water is turned on?

A water hose recoils when the water is turned on due to the principle of conservation of momentum. As water rushes through the hose, it exerts a force in the direction of flow. According to Newton's third law, for every action, there is an equal and opposite reaction, causing the hose to push back or recoil in the opposite direction. This effect is more pronounced if the hose is not anchored or held firmly in place.