There are 3 bonds:
- electroplated: abrasive+nickel layer on metal blank - used for cutters, points, dies.
- metal: abrasive in copper+nickel, may be uniform block without support (blank)
- resin: abrasive in resin - may be may be uniform block but in 99% requires support (blank)
wear out rate depends also on abrasive, i.e. if it self-sharpens while polishing (Poltava, GE/DI diamonds), or just drops out of the bond, like cheap Ch... oriental diamond powder.
there's no reason to make electroplated sharpening stones, except you want to make customers happy seeing cheap stones seating tightly on their places. if at the same time these stones sharpen smth - customers are happy squared.