Why is it necessary to have an understanding of modernism to appreciate Waiting for Godot?

I think that the question probably needs to be broadened
to include "post- modernism," as well.  In the end, Beckett's work is a modernist/
post-modernist work because of its most basic assertion.  The idea of these characters
waiting for a dinner guest who is presumably never to arrive is a symbol for where all
human beings lie.  Beckett does not depict a redemptive picture of human beings, or one
where there is totality present in its final answers, or one where individuals come to
some massive self- realization located in the realm of the subjective.  For Beckett,
there is a belief in what Woolf said in that "All human relations have shifted."  This
is where the Modern elements are located in the work.  Individuals in the modern setting
are ones who "wait" for the answer, whatever the
answer is.  The fundamental precept of the Modern era is an embrace of the
idea that there is little in way of transcendent, unifying principles that can
automatically provide meaning to individuals.  Rather, individuals are set amidst a
setting where meaning is obscured and challenging.  The Modern setting is one where
individuals have to identify for themselves what defines consciousness and being in the
world and in this, Beckett's work speaks loud and clear.