I was practicing ippon seoi-nage(Spelling

), the other week and I heard my coach say, "Only 14,000 times till it builds in your muscle memory." Now I don't know much, if anything about this subject but, I would right be saying that muscle memory is to be able to perform a movement without conscious though, like walking.
Does anybody have any other numbers and evidence to back that? I have no idea what to type into google.
