They do not prevent bad stuff from happening. They are for after the bad stuff happens. And bad stuff happens.
The ones at my business alert me and a relative who rides a desk at night. To date we have managed to get the cops to nab 14 out of 14 people with bad intentions (junk yard and car lot)
Cameras alone are just to see what happened. cameras being watched with a local police force that responds in 5 minutes or less is a very effective crime stopping tool.
It also helps that we have so many cameras you are being watched from at least 3 sides at all times. I’ve even added a few with ai that will track you as you walk around.
I’VE TWO DOGS....THEY LET ME KNOW WHAT IS UP.