What is key to realise about the work of Beckett is that it is linked to a literary movement entitled the Theatre of the Absurd. This was a literary movement that questioned the value of life itself and proposed that life is actually much more bleak and depressing than we would believe. In particular, works that are attributed to this literary movment try to make the audience see that life is joyless through challenging our normal expectations of what we have come to associate with a play. This is why Beckett's works involve little plot and deliberately in places show how language can become meaningless and insignificant.
However, it would be worth considering how the metaphors that Beckett employs become very relevant to his purpose of showing life as nothing more than an absurdist fantasy. Beckett presents us with action that occurs in a single room and with characters who face a monotonous existence that is only characterised by hatred and misery. This is the central metaphor that runs throughout the play as our life is compared to the life of these characters. As such, we can analyse Beckett's metaphors based on the way that they act as a vehicle for presenting his Absurdist philosophy.