Saves large amounts of public money, cuts bureaucracy, increases road safety.
At the moment a whole government department issues pieces of paper for us to stick in our windscreens. If these are exchanged for MOT discs issued when the vehicle is tested, then the vehicle can be immediately and visibly identified as roadworthy. Money can be saved on issuing tax discs. Lives could be saved by removed unsafe vehicles. The tax revenue can either be charged as part of the MOT fee, or can be added to fuel to charge road users according to usage.