MTC Group — Bus not starting off from the first stop and going through other routes

46g, by morning 6.06am, which started off from Mullai nagar depot, did not go through it's usual way (central avenue road) instead went through east avenue road.
Another 46g without starting from the first stop (mullai nagar depot), started off from the vyasarpadi depot. If the bus won't go through it's specified stops, then why are those bus stops marked. Public transports are for public's convenience. But drivers are riding in their convenience. Please take appropriate action about this. Thank you.