The road has been bumpier for their humanoid counterparts, for a number of reasons. The simplest explanation being that "flesh robots," I.e., humans, are difficult to imitate--we're just too darned complicated.
至於人形機器人則發展坎坷，原因不一而足，最容易的解釋就是，人類這種「肉身機器」實在太過精密，很難仿製出來。