Elevation makes a difference
I've found that many Wi-Fi hotspots in outdoor areas have very poor signal strength because the access point antennas are mounted relatively low to the ground, such as near the edge of roofs. The antennas propagate radio waves that must slice through people, buildings, and other obstacles to reach the users. Because of the resulting attenuation, it's generally better to install the access points (or just the antennas) higher up on light poles if they are available. The problem, however, is that it's difficult to run cabling to these higher mounting places. Thatís when mesh network technology comes in handy.