Often, you connect a wire to a wrong input or output. Today, fixing it requires wiring to the new location and manually deleting the old piece of wire. The only exception is two-input functions with both inputs already wired, where you have a keyboard shortcut for swapping the wires.
A much more natural and general method would be this - if you use the wiring tool on a wire source or sink and then on another, the wires should be swapped (or if there's only one wire, it should be moved).
In this example I wired the 7 into the wrong input and I want to move it one input down, so I:
1. Click the top input. This "grabs" the wire, so to speak.
2. Click the bottom input. This moves the grabbed wire to that input.