Because it look a bit like the bird, which is tall and slender.
A crane is: a tall bird of the Order Gruiformes, Family Gruidae, with long legs, long neck and a straight bill. They are similar in appearance to herons. Cranes are often depicted in Japanese art....
A crane is either a type of bird or it is a machine that can dig, move, create, or destroy, depending on their type.
It helped people build building's/scyscrapers