Many years ago, I was driving my second 8' grounding electrode up in the mountains, on very hard terrain one day and using a 12 lb. sledgehammer and was getting only about 1/4" per hit after the first two feet, After, a good 3 hours, I was soaked with sweat and in another couple of feet, but I was finally getting nearly 3/4" per hard wack. I was almost all the way flush and pleased as punch as I wasn't going to let it beat me. I stopped to take a breath, then raise the hammer to give it the few last swings and as I stepped back, I stepped on something that hadn't been there before. It was the point of the grounding electrode. It had come up about 4' from where I had started hammering it in. Then later years, when I became an electrical inspector, I told this story to electricians in the field. One day, these two guys, who were contractors came in and said, "You know Vic, when you told us about that ground rod story, about it coming back up on you, years ago, we figured you were full of $hit but yesterday, we were using our portable electric jackhammer to put in the ground rods up at the house you're going out to inspect today and guess what, the same thing happened to us. We're sorry we ever doubted you. It was just so hard to believe something like that could really happen.
Oh, to the guy that is cutting off grounding electrodes, I carried a grounding electrode tester as an inspector, that could register the grounding effect of the grounding electrodes and it would tell me their length as I had been a contractor and at times had to cut off a little bit of the end of the rod to get the clamp on but I always left the piece in the panel for the inspector to see with a note, explaining my action. They never gave me any trouble over that. The intentional shortening of a grounding electrode in Washington State can and usually does, result in the loss of one's Administrator's (contractor's) license, just so you know. I'm not sure about other areas. What was dumb, was when I found the metal cuttings by the garage or side of the building where their truck had been parked where they had cut the rod or finding the cut off piece out in the weeds if I walked the area when I could see the cut marks in the top of the metal. It's very hard to hide, hacksaw blade marks plus driving galvanization or copper into the head of the rod, definitely leaves a different mark that one that has been cut doesn't have It's just tricks you learn over the years.
Vic