When you have to go underneath the cube and move it to the left again and again until it stop moving to the left and reduces of size on the same length. Or did it perhaps hit an invisible wall? I'm not sure
Viewing post in Scaleshifter jam comments
The way you scale things depends on your position relative to the center of the object you're trying to scale. If you're to the left of the center and you move to the right, once you cross the center, you'll start to expand the cube instead of compressing it. The cube can't be stopped by anything.
I hope this helps.