The ComReg Donut Rule:
Take the traditional hollow centred donut. Put it on a map of Ireland. The ComReg wireless rules state that if you want to operate a wireless licence, the hollow centre is the area you can operate in and the doughy outer ring is the interference zone. You cannot operate in the interference zone and neither can anyone else. Stick a lot of donuts on a map and you can see that there is a lot of doughy bits on said map. Nobody can operate there because ComReg thinks operate on the same frequencies will interfere, this despite the OBVIOUS fact that people can operate competing services on the same spectrum and not interfere.
Look at the massive amounts of space in this country where service providers CANNOT go to even if there is massive demand because donut loving Homer Simpson is in charge of spectrum allocaton rules in ComReg.