Exactly! Just like having a stammer doesn't make you a bad communicator. It's only one tiny part of communication. Some people stammer. Some people have a lisp. Some people mumble. Some people speak too quietly. Some people shout. Some People Swear Too Much. Some people are shy. These are all small elements of communication and being bad at only one or two of them (including a stammer) can't define you as a communicator.