What scares you the most on the road? This may be idiotic and not supported by statistics, but I’m afraid of deer jumping out in front of (or into the side of) my car, which has happened to me. That’s followed closely by the fear of some moron blowing off a stop sign or red light and running into me, which has also (sort of) happened to me.
The two are different degrees of the same thing and the fear comes from it happening suddenly, unexpectedly, and with no time to react. I think the deer thing scares me more because deer are too stupid to know not to run onto a highway. Other motorists at least should understand not to do the same against a traffic signal, although some of them appear to be as stupid as the deer.
Then there are motorcycles. I have nothing against them or those who ride them but I’ve personally seen enough people badly injured riding them, I stay away. So what happens when two of my highway phobias come together literally? Yikes! At least those guys were only hurt, but still.