Brake and derailleur cables are extremely difficult to cut with a standard pair of wire cutters (sometimes called side or diagonal cutters); when it is finally accomplished, this process usually leaves a frayed mess of the inner cable, which is impossible to slip through the cable housing or the hole in a fastening bolt. In addition, the jaws of these cutters are made for cutting copper electrical wire, and will become notched when cutting steel bicycle cables.
Cable cutters specifically designed for steel cable, on bicycles or elsewhere, are available at prices low enough to eliminate this nuisance. They are generally similar to regular cutters or scissors, but have extra-hard jaws, each of which carries a v-shaped notch. When cutting a cable, the notches overlap, trapping the cable in a diamond shaped hole with sharp edges, which becomes smaller as the handle is compressed, thereby cutting the cable easily without fraying and with no damage to the tool. They are also useful for cutting the cable housing, although they often close the inner sleeve, and it needs to be re-opened with a piece of cable or other means. Sometimes their use leaves a small burr on the housing which may need to be filed off.