Aside from the danger of unexpected electrical fun, those cut off bits of wire then to go flying at fairly high speed and can injure your eye(s), so wear safety glasses! Or the piece can get caught in carpet and thence into your foot when you step on it barefooted. This isn't theory, I've managed to do that. Not quite as much unfun as stepping on a 2N3055 pins up barefooted, I have that 2N3055 mounted on a nice stained oak board, with the blood still on the transistor case.
