In traditional wheel/rail operations, the wheels eventually wear out. In addition, the resultant grit on the running surface of the tracks causes abrasion of the railheads.
Example: Each InterCity Express (ICE) train wheel alone loses about 68 kg/150 lb of steel through friction from driving and braking before it is withdrawn from service, usually after two or three years (an entire ICE train loses about 8 metric tons/17,600 pounds). TGV and conventional Shinkansen trains are equally subject to wear and tear.
Data from the Shanghai Transrapid Maglev project indicates that operation and maintenance costs are covered even by the current relatively low volume of 8,000 passengers per day (due to the inconvenient location of the line in the suburbs of Shanghai that lacks attractive for potential riders).