It may have been a while since you had someone sit with you in the car giving you instruction, but perhaps you recall being told to look into roads that join traffic light controlled junctions as well as looking at the red-amber-green?
This video is a fine example of why you want to watch other roads as well as lights. In case someone (this time, a Rex Group van driver) runs the light because they are in a hurry or distracted (phone? fiddling with radio? tired? simply lost concentration?).
