This is why your cell phone works in the middle of nowhere

Right next to that oil tank perched up on that hill was this little hill with a shit load of wierd looking antennas. And this is the middle of nowhere, and I mean nowhere desert. What I want to know is why do they have a fascination with putting shit on top of shady looking plateaus? There is plenty of flat desert that they could put this shit on where they wouldn't have to worry about rock slides taking their shit out...