It's "Priority", not "Right of Way"
The term "Right of Way" is actually defined as the right to "pass and re-pass" across a piece of land, ie you can do so repeatedly without needing to ask (or be given) permission.
"Priority" means that you are legally entitled to go first, so if a pedestrian steps out into the street in front of a car and gets knocked down, they can't complain that it wasn't their fault because they had Right of Way. There are exceptions, of course, for example at a Zebra Crossing where once the pedestrian has set foot on it, they *do* have Priority and vehicles MUST stop for them.
Similarly, at a roundabout, you MUST give Priority to vehicles coming from the right, if you fail to do so and this results in an accident, you'll be liable.