Earlier quoted context omitted.
In most areas taxi-companies use a zone-based system where cars will flag what zone they're in (rarely automatically using GPS and more often via button presses) this is an effort by the cab company to keep their vacant vehicles well distributed to keep a high response rate and increase customer turnover. It also happens to have the side benefit that an operator watching the flagged zones would be able to see this ki…
But there should still be some override that would allow for a bunch of taxis to converge at one spot. Say a sporting event just got out, there's going to be a lot of people looking to catch a ride home. If you don't want all of those customers finding another ride, the system should have no problem dispatching drivers from other zones to pickup. Having a bunch of fares popup at the same location shouldn't be a major…
Backpressure.
Add artificial delays to the queuing time, increasing for each taxi.