Driving can be difficult at the best of times. To drive safely requires focus, patience and rational thinking. Anything that affects a person’s ability to exercise these things reduces their ability to drive safely.
This is why anger is such a problem. A driver who is agitated has insufficient mind control to be fully safe.
What upsets drivers?
An angry driver might be mad about something that occurred while driving, but often they were already upset before they got into the car due to something unrelated. For instance, their child refused to put their shoes on, leading to an argument, and now the parent is late for work. Or they went to get into their car only to find their spouse had failed to return the seat to its usual position after borrowing it for the weekend. These are tiny issues, but they can turn into a major issue when a driver carries that anger onto the road with them.
Other small things can exacerbate their anger. For instance, the light turns red just before they are about to pass. Or another driver leaves it late to indicate causing them to brake suddenly.
When an angry driver crashes into you, they may come out with a host of reasons why the crash was not their fault. They tell you that you did this, or should have done that. Yet, none are a valid excuse for them allowing anger to affect their driving. A driver needs to control themselves and stay calm when in charge of a vehicle. If they do not and injure you as a result, you need to understand how to hold them responsible.