It is said that a picture is worth a thousand words.  So, it naturally follows that four panels of a comic would convey the same information as roughly four thousand words of a story.  However, no excerpt of that length would spend the entire time describing a single static situation.  The story must transition from one segment to another.  Comics must also transition from one segment to another.  The Weekly Roll and Looking for Group both demonstrate a variety of techniques used to transition from one panel to another.