What good are security cameras?

[Johann Jells]

I had an intruder on the fire escape of a multifamily last night and the tenants are suggesting cameras. I can't see what good they are except as security theater unless you have someone watching 24/7. So after a robbery you get to see footage of a masked and unrecognizable person wandering your common areas. What good does that do anyone? In my neighborhood people post Ring clips of package bandits all the time, these cameras are not a deterrent to the porch pirates, why would they be to burglars?

Then there's the cost, besides thousands to purchase I'd have to get a broadband service at the property just for the cams, at like $70/month. So why is this so popular???