Re: Sometimes it's the user
When I was a kid of about six or seven, I was given a new Space Watch for Christmas. This was basically a normal analogue watch with two numbered discs in place of the hands, and a stainless steel case with two small holes to view the numbers as they progressed past, in order to tell the time. When I put it on my wrist, it immediately stopped. Put it on the mantlepiece, and it would start working again. On my wrist - stops dead, on the mantlepiece, desk, bedside table, anywhere - starts working again. Sent it back to watch shop, no fault found. Several trips later, they gave up and sent me a normal wristwatch, which proceeded to exhibit the same phenomenon. Other members of my family could wear it successfully, but not me. Gave it to my sister, and was given a pocket watch, which worked OK as long as I kept it in my shirt pocket. I was the only kid at school who wore a pocket watch and chain, much to the amusement of the teachers. Problem went away as I grew older, but never did find the cause.