What I was mentioning is that today, what used to be a security function - motion sensor, has become a 'courtesy' function - turning on walk lights for guests etc. Your description is accurate. It is like an AC coupled response.
What I was talking about was disabling the ability of an intentional intruder from 'testing' the sensor early. Walking the space, finding range, sensitivity to motion, etc. IF the sensor has immediate response, is easy. IF sensor has a delayed or weird response time, is very difficult to correlate the activity to the sensor's response.