Speed Cameras are put up to collect money. A couple of years ago a bypass opened in Essex with speed cameras on from Day 1! No history of accidents, just cameras straight away. Near where I live the local police were fed up with bikers giving 'V' signed to cameras which took a picture of the front of the vehicle ie no number plate in view. They formed a special unit consisting of a car and two motor bikes to chase up the 'offenders'. Meanwhile the clear up rate for burglaries stayed nice and low and plenty of people were driving around in cars with only one headlight working and loads of uninsured, no seatbelts etc. But the targets wwre met so that's alright then!