I think being alone all the time is the main reason people start talking to themselves.

It's not a problem until you start answering yourself

Or start posting shitty OPs all over the site

You wouldn't talk to yourself if you had a volleyball to talk to.

Biggest problem with the habit of talking to one's self is that you are just talking half-thoughts and jibberish. Then when you actually get around to talk to real people your conversation is that jibber half-thought shite.

Actually, only if you argue with yourself and then lose the arguments.