It's when they slam their brakes on and stop at a junction, even though there is no other car for miles...some people just don't think further than their front bumper when it comes to making driving decisions.
But I've also been the recipient of this, someone coming on to a roundabout a bit eager so I delay my decision to pull away, next thing I know the woman behind has hit me. She was doing all of 3 miles an hour so we just swapped details and left it there. I was more bothered that it was raining and I was already late for work!
You'll have it fixed and running in no time.