It takes more refractive power to focus rays from a closer object since the rays are more divergent when they arrive at the lens. Since the nearsighted eye has excess refractive power that focuses parallel rays somewhere in the interior of the eye, bringing the object closer will cause the focal point to move toward the image-detecting retina and improve the vision. For the extremely farsighted eye above, things just go from bad to worse when you bring the object closer since you need more refractive power and you didn't have enough to begin with.
Optics for Optometry