Very good question as technology sometimes is over priced for what it can do.  Robotics however in guarding a location are a great way to reduce human error. It's not when the guard falls a sleep, or plays on twitter instead of watching your location. It's when he eventually gets fired and goes out with his friends who then share eveything about your location. Robots don't do that. Yes they are cost effective - a robot saves about 70,000 a year over a traditional guard.  Id say that is a savings in itself. More importantly is they can work in all weather conditions. Now certain locations maybe more of a challenge than others but normally we have seen them deployed on a host of terrains.   Hope that helps!