Just put your smart lights in "Away mode" when you go on vacation. Certain lights will turn on and of to simulate your presence in the home.
We can also link actions to your security system. Let's say fire is detected at night. Smart lights can use that as a trigger and light up escape path automatically.
If there is intrusion, smart lights can activate scene where outdoor lights will start flashing and all lights inside will turn on. That can alert neighbors and scare the intruder.
Smart lights can be activated by schedule or triggers and make your home safer and more secure.