Why do people use hydroponics?

as far as i am aware hydroponic gardens are used because there is a lower rate of desease on plants, most deseases come from the soil. hydroponics eliminates this. they are also used in parts of the world where normal farming is not possible due to its quick turn-around time and relatively low water consumption. a typical crop can use 75% less water (less evaporation) and take up half the footprint. sees how the roots are not growing as big to find nutrients more energy is used to grow the actual plant.