Down to the quantity of traffic on our roads which makes them bad. The roads aren't big enough and there isn't enough room for all the cars. You drive abroad and see very few congestion problems on the motorways. You try to drive on the inside lane and you can't because its full of morons doing either 60mph or there is a bunch of people all driving along together making it very hard to cut in.

Oh well.. Lets hope our road tax will actually get used on the roads in future.