Why are box turtles able to escape from their enemies easily?

 Box turtles are land dwelling creatures found in mossy areas of the forest, or other damp habitats. Box turtles have a high, domed carapace or upper shell, and a lower shell or plastron with a hinge between the front and rear parts. When a box turtle is frightened, it pulls its heads, legs and tail into its shell, and slams the carapace and plastron together. It is now safely inside a ‘box’ formed by the tightly closed shell, and its enemies will find it very difficult to get at it.