Routh-Hurwitz Stability Criterion

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I started to an study introductory course in control theory. I understand that all the roots in the (system's) transfer function's denominator should be on the left hand side of the s plane in order to be stable. And I can use any math software such as Matlab to find all the roots of a polynomial and see if they are all negative. Easy. Then we learned about Routh's criterion to check stability. My question (or what I didn't understand) is: why to use such a (complicated) criterion, when (instead) I can use Matlab and directly find the roots of the polynomial? It is not much easier? I probably missed something deep...