If the appliance developes a short and it is grounding out to the chasis or frame of the appliance you will get shocked if it is not grounded. For example, A refridgerator. If a wire is rubbed bare and touches the frame or one of the wires in the compressor motor goes to ground, (shorts out inside the motor) you could get shocked if you came in contact with the appliance near the grounded situation. Just because there is a short somewhere does not mean that a fuse or breaker will blow. It all depends on how big the "ground out" is. If you have a ground that is not real big there is a good chance the breaker or fuse will not blow and you will get shocked if you come in contact with it in the right place.