First, the entire written text of Hamlettakes more than four hours to perform, making it Shakespeare's longest play. Most staged versions cut this down substantially to fit the typical two hour play length. That's not to say that all 4,042 lines are never staged in a single production; but,...
First, the entire written text of Hamlet takes more than four hours to perform, making it Shakespeare's longest play. Most staged versions cut this down substantially to fit the typical two hour play length. That's not to say that all 4,042 lines are never staged in a single production; but, that is rare to see. So, if you are reading it, you are getting the full version, unlike (most of the time) if you see it performed.
Second, a staged version forces an interpretation of the play: is Hamlet to be depicted as mad or just pretending to be mad, for example? How Freudian should the staging be: should it highlight or downplay Hamlet as sexually attracted to his mother and jealous of Claudius for marrying her? Should Fortinbras's role be downplayed or accentuated? How somber should the sets be? Should the action be put into a more contemporary setting to highlight political corruption in today's world? All of these decisions are made for the playgoer ahead of time, whereas readers must use their imaginations and interpret for themselves when they read the text alone.
Attending a play can have an energy that reading a play alone might not. A playgoer reacts to other people in the audience and the actors.
Finally, much can be communicated—and the play made either more humorous or more serious—by the gestures, facial expressions, and costuming of the characters in a staged version. Again, this dimension can only be imagined through reading and is often in danger of being lost.