What the hell was with the alarm system?

That plot had to be the most ridiculous thing about this movie. The undetectable killer and unlikely kills are more acceptable because they're standard horror genre things, but the alarm system was just nonsense.

First, they start off with Stephen Weber setting off the alarm, which the family apparently isn't even aware exists. The alarm company calls them, they say they didn't know about the alarm so they don't have a password, and the guy on the phone says the police will be there and help them.

Then the alarm stops, and that's the end of it. We don't see the police show up, there's no resolution to this first event, for all the security guy knows he was talking to an intruder who just killed the whole family because he didn't stay on the line or make any attempt to identify the caller.

So after that scenario, we're left to assume the police showed up, talked to the Gates' and they resolved this whole false alarm situation offscreen.

Then after Stephen Weber shows up in the house and they call the police, they talk to the police, lock up the house, increase their security measures and even have a police car outside watching the house for them overnight.

Then when Stephen Weber makes his final stand, the mother hits a button on the alarm to alert them of an intruder. Stephen Weber hears the phone ring, answers it, and gives his password for the alarm. The guy on the phone says OK and hangs up.



So does that mean they never transferred the alarm service into their names with their own password? Did the guy at the alarm company contact the police because it was the wrong password and they just hadn't shown up yet? Why hit the alarm button instead of picking up a phone and calling 911 so you can give them specific information about the situation?