A propagation map lights up enormous coverage holes over forests, water, and farmland. Optimizing to fill the biggest holes builds towers nobody uses. The signal that drives ROI is not the size of the gap in square kilometers but the unserved demand inside it — population density, daytime vs. nighttime occupancy, points of interest, and the corridors people move through.
An agent planning coverage should overlay the gap geometry with population and POI/movement data, weight each hole by the demand it would actually capture, and rank candidates on incremental served-traffic-per-cost. A small gap over a transit corridor or dense neighborhood routinely beats a vast rural hole. This reframes 'coverage planning' as demand capture, not map-painting.
Caveat: regulatory coverage obligations and emergency-service mandates can require filling low-demand gaps regardless of ROI — separate the obligation-driven builds from the demand-driven ones rather than letting one logic distort the other.