There just certain parameters that they don’t work well in and knowing them helps alot. Like if the camera/ radar is iced over or glare from the sun or a leaf blows past?. If the road markings are faded, if you try and change lane and don’t indicate etc etc.
I use adaptive cruise alot and it is great the new car has cut-in protection and it slows down if it detects a car may change lanes and slows the car down 95% of the time it’s right as then they pullout. Quite amazing really my golf mk7 never had that. So one had to aim the car at the other car for the radar to pick it up once they started to cut in to the lane.