These days most homes have several easily saleable and portable items: televisions, radios, videos, cameras, etc. But whatever one owns, who wants intruders "turning over'' one's belongings anyway?
A police security officer recently put the point of alarms to me rather succinctly. He said they were to a burglar the opposite of an open window. If one does not want a working alarm, his advice was at least to display an empty alarm box in a conspicuous position.