I think Mr. Terrio and Bladite, perhaps without knowing it, have applied the basic System Engineering "V" (letter "v", not Roman numeral) to analyze and procure their home security solutions.
In a nutshell, you start at the top left of the "V" by determining what your "operational requirements" are. In this case, a secure home. After that, you develop potential solutions to satisfy these requirements. It need not always be a material solution or a single material solution, but could be changes in procedure or multiple material solutions (dogs, alarms, lights, and/or guns). If a material solution(s) is called for, then technical specifications are developed for the item(s) that are required. This devolution of requirements is the bottom of the "V". Once the item(s) are procured (manufactured, purchased, etc), then they should be tested against the technical specification ("Was it built right?). This is where we go back up the right leg of the "V." If it meets the technical spec, then it should be tested against the operational requirement ("Did we build the right thing?"). This process if both iterative and recursive, and eventually you are able to answer "Yes, we did build the right thing." Then, and only then, you can state that your operational requirement is met.
Too many times, folks skip strait to the solution without really examining what the real requirement is and consider alternatives other than the obvious that might meet the requirement better and for less money. Kudos to JT and Bladite for "getting it!" ...if they are still awake after reading this.