happens on irc and internal channels. a context is set with the first message and it picks up direction as messages pile up. unlike in person conversations where you can cross question and interrupt the other person, these text based conversations have very less scope of diversion from the direction they have taken on.
i offended some people on irc doing that unknowingly, so please don't do that. let that conversation reach a conclusion then ask your questions which were not directly related but around the same topic and ask one question at a time.