We turn ours on at night when sleeping. If a door or window opens it goes off. There’s a delay on most of them so even if Mz Rothschild had come home and opened the door, she could punch in the code before it went off. Most of them have key fobs now. We can turn ours off before we ever open the door.
Careful. Lots of crooks have gadgets that can unlock car systems.
Little or no difference in your home system.