What is the difference between "change" and "unstitch"?

Solution 1:

In your example, "to unstitch" is used figuratively. "To unstitch", in its literal sense, is used to express the action of taking the stitches (the thread/cotton joining parts of a garment) out of a garment. This, of course, reduces the garment to its component parts. So "to unstitch" means "to take apart" - "to take apart" differs from "to change".