Looks like it accidentally got over the edge and fell down the stairs and into the fountain. Without arms or legs, it was goodnight, Irene. Dirty Harry Callahan’s cautionary motto comes to mind. “A man’s (Robot’s) got to know his limitations.” IMHO, the fault is the programmer’s, or the building maintenance managers. The robot should have been programmed to avoid stairs; or a barrier should have been installed to keep the robot out of trouble.
HAL 9000: I know I’ve made some very poor decisions recently, but I can give you my complete assurance that my work will be back to normal. I’ve still got the greatest enthusiasm and confidence in the mission. And I want to help you.