How does night vision motion detection work?

Maybe I am not understanding how night vision motion detection works. I have a Stick Up Cam Elite (wired, POE), that works great during daylight hours. The one motion zone I created does exactly what it is supposed to do. I have found night time motion detection is not triggering for vehicles (myself) pulling into our driveway at night. I have the camera mounted high up on the front face of my garage facing the driveway and the alley it abuts to. I get home from work at night, and so far in the past week I have only been able to get the motion activation/recording to trigger if I drive very S L O W L Y into my own driveway. Otherwise if I pull into the driveway and garage at regular speed, even though I am driving directly under the camera, it doesn't trigger or record anything. Oddly, there have been a couple of motion events from animals at night that worked just fine. One was a raccoon, and the other was a black cat, both of which walked into and through the driveway area, and triggered the camera without any issues. This leads me to believe the camera has issues detecting movement of inanimate objects like vehicles, but does just fine with living creatures like people and animals. Is this because live animals/people give off more heat and make it easier for the camera to recognize quicker? I already went through a support telephone call with Ring and everything is set correctly in terms of motion zones, sensitivity, alerts, installed "outdoors", etc. I have 2 lights on either side of the overhead garage door that stay on all night and provide a decent amount of light for the area covered by the camera. I tried using both the color and black and white version of night recording with the same results. I am trying to decide if the camera is defective and I should exchange it, or is that just how night vision on these cameras work? Any feedback is appreciated. Thanks!