WHY?
the ticket collector has to monitor inflow of passengers and see if they get off at their stops therefore it is needed to make the conductors job easier
HOW?
the inflow could be monitored by logging the footfall into the bus and since every seat except the first ones have a back rest in front of them and the conductor could input where the passenger on the seat number could be getting off and the display or warning system tells the passengers when their stop is going to come.
