Solid salt thrown into water after a while after still dissolving is evenly distributed throughout

Solid salt thrown into water after a while after still dissolving is evenly distributed throughout the liquid. How can this be explained?

If you throw solid salt into water, at first the interface between salt and water will be clearly visible, but over time, this border will be less visible, and then it will disappear altogether and the salt will dissolve in water. This is because the water and salt molecules begin to swap places. Molecules constantly move chaotically and spread throughout the entire volume. This phenomenon is called diffusion, when molecules of different substances penetrate penetrate each other. If the temperature of the bodies is increased, this process will go faster, because the molecules will begin to move faster. This phenomenon is very important, for example: the oxygen produced by plants is distributed evenly into the environment.