The truth is there are a couple of reasons that are really important. I've had alarms before, but I've never felt safe.

The reasons are this:

1) There are a lot of false positives. That's when the alarm goes off because the cat walks in front of the motion sensor. You think there's someone breaking in, but actually there's not. That happens a lot. It happens so often that the police no longer come rushing to your home when they're alerted by an alarm because they, too, know it's probably a false positive. In fact, they'll require you to get eyes on whomever is in your home.

2) Imagine that here you are - you secure your home with a security alarm and the alarm goes off. You're frantically calling the police and they're telling you, "Well, is there someone in there? Could you just go verify? Take a look for us and let us know. If there is, then we'll come out." If there is, if you do say, "Yes, there's someone in here. Come get us," they're not going to be there in 3 minutes. They're not going to be there in 5 minutes. They're not going to be there in 10 minutes. The turnaround time, in general, is about 15 minutes if you're in a good neighborhood, right? You can't count on this alarm going off and the police coming to your rescue. They may get there eventually, but it's going to take some time. Until then, you or your family are on your own.

3) It’s best to keep all of that out of the home. Don't let any burglar, don't let any creepo, don't let any rapists, don't let Sasquatch get in through that door or that window. Keep them out there and you're happy as a clam.