A problem that sometimes occurs during disassembling is an unslotted length-2 technic axle being stuck in some axle hole that is a dead end, i.e., you cannot push the axle out with a longer axle from the other side, e.g., like this:
With longer axles, you usually have a better grip and more leverage to get them out, and slotted axles can be grabbed by the slots. But an unslotted length-2 axle may be quite difficult to remove.
Are there any tricks to do this?