beacuse the driver has passed a test up to a certain stanard and is qualified to drive on the roads just as anyone else is. If you are good enough to pass the test, you are good enough to drive a car (without having to broadcast you are a fully qualified driver)
Its the law in northern ireland to use the similar "R" plates for a year after passing, and it works very well.
People tend to be more aware of drivers with them and give them a bit more leeway if they are hesitant or stall, or dont move off quick enough at a junction etc
Speed is also limited to 45mph for the first year after passing the test
thats what i though chazza,
though i know what ethel means, but i would have thought that people who'd do that are not common.
i realise that neutrogena, but its not saying you are not good enough to drive on the road, just saying you are inexperienced and to make other drivers aware of that.
i think norm is probably right about embarrassment