BAIT!

There are many times in the play when baiting is used by the characters to get what they want out of the other characters. Polonius uses Gertrude as bait, King Claudius and Polonius use Ophelia as bait to catch Hamlet, Polonius uses Reynaldo as bait to spy on Laertes, etc. Using the bait often times did not prove to be successful and would just result in a more confusing or disasterous situation. They only time when using bait actually worked was when Hamlet used the players and the skit to catch King Claudius. Hamlet used the play to tell if Claudius really killed his father, and when the king left in the middle of the play in a rage, Hamlet knew his bait had worked. So, for everyone beside Hamlet, the bait did not work. But of course since this play revolves around Hamlet, his bait was successful.