Watch takes pictures of itself.

Frequently I find images in Photos on my iPhone which are screenshots of my Apple Watch.

I have no idea why the watch is taking pictures of itself. I suppose it could be that somehow I am accidentally pressing both the button and the crownwheel at the same time, but I'm not 100% sure that is the cause.


Could the watch possibly take pictures of itself in response to some error or exception in the background?


Or am I just not realising that I'm doing it myself?