Criticism of the Space Shuttle program stemmed from claims that NASA's Shuttle program failed to achieve its promised cost and utility goals, as well as design, cost, management, and safety issues. Fundamentally, it failed in the goal of reducing the cost of space access. Space Shuttle incremental per-pound launch costs ultimately turned out to be considerably higher than those of expendable launchers. By 2011, the incremental cost per flight of the Space Shuttle was estimated at $450 million, or $18,000 per kilogram (approximately $8,000 per pound) to low Earth orbit (LEO). By comparison, the comparable Proton launch vehicle is said to cost as little as $110 million, or around $5,000/kg (approximately $2,300 per pound) to LEO, despite not being reusable.