In order to yield photorealistic renders, you need to set up the materials correctly.
The Render quality and performance parameters are classified into specific groups such as metal, glass, brick, mirror, etc. These render styles can be assigned with drag and drop to any material. The result can be assessed in the integrated render window.
The command does NOT change the size and texture of the materials, it replaces the material quality parameters only.
In addition to the sets, custom settings can be made, but the use of custom properties is primarily recommended for users with rendering experience.