One inherent benefit to manufacturers by adopting WRC regulations was removing the need to mass-produce road-going versions of the cars that they competed with, under the previous rules for homologation. This meant that vehicles such as the Escort RS Cosworth and Subaru Impreza Turbo no longer had to be mass-produced for general sale in order to compete at World Championship level, and thus acting as a means of attracting increased competition and involvement by manufacturers.
Adopting WRC regulations provided manufacturers with a benefit: they could avoid mass-producing road versions of their competitors' cars for homologation purposes. This allowed vehicles like the Escort RS Cosworth and Subaru Impreza Turbo to compete without needing to be widely available, leading to increased competition and manufacturer participation in the WRC.