In preparation for embossing smooth leather, the leather is frequently sanded (buffed) first on the grain side to obtain a uniform surface and to make skin damages invisible. Subsequently, a binder-based colour layer is applied and a uniform grain embossed.
Such leather is then referred to as "Corrected Grain". It is cheaper and feels stiffer and colder due to the thick colour layer and the fibre compression of the embossing. It is also less breathable than porous leather.
There are also corrected grains, which are only slightly sanded and embossed and feel soft and warm. But they are rare exceptions.
Embossed and buffed leather. The hair pores are buffed and embossed away.
After removing the surface colour layer with a solvent:this leather was buffed, pigmented and embossed with hair pores optic. Visible hair pores alone are not yet a sign of good leather quality.