What happened was car A started in the right hand on ramp. Then a big truck came roaring through the intersection at high speed. Car A choose to stop. Unfortunately car B behind him started after A trying to get through with A ahead of the truck. Car B wasn't looking at A and ran right into him from behind. I was taking the left and saw A's rear bumper on the ground.
This must be about the most avoidable car accident. If you are behind someone on a ramp waiting to take the right, do not even look out your left window at oncoming traffic. Look straight ahead only and make sure the car in front of you has gone into traffic and you are at the front of the line. Do not even look out your left window until you are at the front of the line.
What people like the car B driver often do which is very bad is they assume the driver ahead will go in a borderline window of opportunity. They then aggressively try to piggyback tight behind the first car and also get onto the road within car A's chance. Now if A chooses not to go then B has no time to stop and may not even be looking at A when he slams into his rear, a bonehead move causing an accident.
When you consider the time and money lost by being at fault in a car accident, trying to save a couple of seconds by aggressively piggybacking behind someone on a right ramp turn into traffic is not worth attempting.