Procrastination is a significant theme in Hamlet. Hamlet's procrastinating (also called his "delay") is what sustains, dramatizes, and prolongs the plot of his revenge. Consider also that Hamlet delays or simply refuses to tell anyone of his plan and strategy; he essentially procrastinates telling anyone what he plans to do and why he behaves in a melancholy or crazy manner. Hamlet appeals to Horatio at the end of Act One, Scene Five, to ignore any odd behavior. Hamlet is determined to keep his revenge plot to himself.
Hamlet remarks to the ghost that he will focus all of his efforts on revenge ("I'll wipe away all trivial fond records, / All saws of books, all forms, all pressures past," (I.v.99-100). However, Hamlet begins to procrastinate and over-think things. Hamlet is frustrated with himself about this, and yet he continues to delay:
A dull and muddy-mettled rascal, peak
Like John-a-dreams, unpregnant of my cause,
And can say nothing--no, not for a king
Upon whose property and most dear life
A damned defeat was made. Am I a coward? (II.ii.543-48)
Just after criticizing himself for delaying, Hamlet decides to use the play to expose Claudius' guilt, thus finding a way to drag out his revenge plan. Rather than covertly killing Claudius, Hamlet feels it necessary to make this guilt a spectacle: "The play's the thing / Wherein I'll catch the conscience of the King." (II.ii.581-82)
In Act Three, Scene Three, Hamlet has an opportunity to kill Claudius and avenge his father. However, Hamlet, ever the philosopher, can not bring himself to kill Claudius while he is praying:
Now might I do it pat, no a is praying,
And now I'll do't, and so a goes to heaven,
And so am I revenged. That would be scanned.
A villain kills my father, and for that
I, his sole son, do this same villain send
To heaven. (III.iii.73-78)
Hamlet is about to kill Claudius but he decides the situation needs to be evaluated ("scanned"). He determines that it would not be true revenge because if he kills Claudius while he is praying, Claudius might go to heaven.
In Act Four, Scene Four, Hamlet agrees to go to England, further delaying his revenge.
Claudius also procrastinates in dealing with Hamlet. Laertes calls Claudius on this, asking why he would not go after Hamlet considering that Hamlet has killed Polonius (Laertes' father) and poses a threat to Claudius himself:
Why you proceeded not against these feats,
So crimeful and so capital in nature,
As by your safety, wisdom, all things else,
You mainly were stirred up. (IV.vii.6-9)
Claudius responds that he left Hamlet alone for the time being to avoid displeasing Gertrude and because he needs to sway public support from Hamlet to himself before doing anything drastic. At the end of Act Five, Scene Two, Laertes and Hamlet are about to fight, perhaps to the death, but Claudius urges Laertes to wait (procrastinating) in order to follow their previous plan: the duel.
Hamlet accepts the challenge to duel despite advice from Horatio to postpone (procrastinating again) the match because he thinks Hamlet will lose. However, Hamlet finally feels like the time is right to act:
If it be not now, yet it will
come. The readiness is all. Since no man has aught of what he
leaves, what is't to leave betimes? (V.ii.159-61)