Fixed minor typo.

Author: cspencer

S06-routines.pod

@@ -199,7 +199,7 @@ the candidates for these arguments (hopefully memoized), create the dynamic
 scope of a dispatch, start the dispatch, manage C<callnext> and C<lastcall>
 semantics, and return the result of whichever C<multi> succeeded, if any.
 
-Which why we have C<{*}> instead.
+Which is why we have C<{*}> instead.
 
 Another common variant would be to propagate control to the
 outer/higher routine that would have been found if this one didn't