In the context riding/driving, a right of way is given by someone else. If they decide to just go for it, you have to have planned that they will do just that and be prepared to slow or stop.
Priority is similar. If an oncoming driver decides to pass a vehicle on their side of the road, forcing you to stop, you should have had priority and the right of way, but they decided not to give way. Arrogance, ignorance, impatience, incompetence or just plain bad manners. Unfortunately, there is too much of all of these and not enough common sense! But you don't need that to use the highway, be you pedestrian, driver or rider!