$< $> $* $^ ... Not particularly explicit. You also have the very useful substitution rules, like $(SRC:.c=.o) which are probably more arcane than they ought to be. You can make similar complaints about POSIX shell syntax but at least the shell has the excuse of being used interactively so it makes sense to save on the typing I suppose.

That's my major qualm with it however, the rest of the syntax is mostly straightforward in my opinion, at least for basic Makefiles.