Before SWR was formed the chuck of lines beyond Bangalore was in MG.. so technically it was not possible to link Chennai with Interior north Karnataka... KL, AP all are blessed with enough trains to Chennai. After SWR formation, both SR/SWR never cared to run trains beyond Bangalore or Mysore.. If we look, SR never introduced any daily train outside SR territory except to Bangalore. Even SWR wants to connect Hubli with Chennai via Gadag, BAY.. it needs SCR support too! This is 4 zone train so it is very difficult to attain daily status!