What needed to happen for the film and story have ended with Wizard of Oz Dorothy in Kansas?

The film *Wizard of Oz* could not have ended with Dorothy in Kansas because the cyclone that brought Dorothy to Oz had also destroyed her home. At the end of the movie, instead of using her magic slippers to return to Kansas, Dorothy uses them to defeat the Wicked Witch of the West and return to the Emerald City with her friends. There, the Wizard of Oz grants Dorothy's wish to go home, but she must use the power of the slippers to return to Kansas. Otherwise, she would have remained in Oz forever.