Opponents of David Cameron's plan to "privatise" some major roads in England will cite the distinct lack of success of the UK's only existing motorway toll road.
Operating since December 2003, the M6 Toll road in the West Midlands is carrying less than half the number of cars it was designed for.
Local businesses say the high prices - there have been eight rises in nine years - are deterring people from using the 27-mile long route.
But the toll road's operators say the low traffic levels are merely a result of the economic downturn and that the road offers good value for money.
Running from Coleshill, just north of Birmingham airport at the M6 junction 4 in the south, to Cannock in Staffordshire at the M6 junction 11A in the north, the M6 Toll was created to relieve pressure on the ever-busy M6.
It had been hoped that the road would carry around 74,000 vehicles a day.
But usage in the middle part of the last decade was only around 50,000 vehicles a day and has slipped much lower since.
Usage did go up from 41,898 vehicles a day in July-September 2010 to 44,089 in the same period in 2011.
But, on average, only 34,286 vehicles a day used the toll road in the period October-December 2011 - a dip on the figure of 38,405 in October-December 2010 when the weather was more severe.
The road is operated by Midland Expressway Limited (MEL), a private company with the Government concession to design, build, operate and maintain the road until 2054. After this time the road will be handed back to the government.
When the road opened, cars were paying just £2. The latest rise - announced in January this year - has seen the weekday rate (6am to 11pm) rise to £5.50 for cars and to £11 for heavy goods vehicles.
A poll last year by business organisation The Birmingham Chamber Group showed that of nearly 100 local firms, 78% did not use the road because of its price.
At the time, Will Rogers, of the chamber, said: "Many people still feel that the road is still too highly priced to provide a viable alternative to the heavily-congested M6. "For regular users, it's not an economic alternative to the M6."
At the time, Tom Fanning, from Midlands Expressway, said: "The toll road remains excellent value for money considering the benefit of bypassing the congestion on the M6."
Today, Stephen Joseph, the Campaign for Better Transport's chief executive, said: "The M6 toll hasn't worked for motorists, shareholders or the community and there is no reason to think that other toll roads or lanes would do better.
"New roads just fill up with traffic no matter whether they're financed by the Chinese, a pension fund or from public spending."
One way for drivers to pay less - although only 5% less on each trip - is to use an electronic tag system in which an electronic device is fixed to the vehicle windscreen.
All vehicles pay less to use the road at night and at weekends.