Beauty dishes are versatile, photographers can change the quality of the light by selecting a dish with a silver or white inner surface (the silver-coated surface offers a more secular, hard contrast light while the white-coated surface gives a smoother and softer light). You can also control the spill of light with a grid and further soften the light by adding a grid. One of the advantages of the beauty dish over every other modifier is its versatility and affordability.
The Video below from YouTube by Miguel Quiles gives an extensive overview of the use of the beauty dish and its benefits.