BALANCING ISSUE > EFFECTIVENESS OF ADVERTISING
The "effectiveness" of increasing advertising in cities does not justify using it. Especially in the closest cities, their demand of unit's requested raises so slowly over time, that it doesn't make any sense to use advertising to increase the number of units's requested.
ISSUE
The upper limit of "Unit's requested" cannot be reached in the time it takes for the transport to do a round-trip from factory to the city and back.