It's not just humans, I've had trouble generating appendages for other creatures and also machines like robots. Dragons with missing wings and seven legs, robot

It's not just humans, I've had trouble generating appendages for other creatures and also machines like robots. Dragons with missing wings and seven legs, robots with feet that have feet that have feet. Stuff like that. So far the best technique I've found is to fix in retouch photos, or to hide their hands by e.g. prompting characters to have their hands behind their backs.