Originally Posted by horatio
Same reasons the Klingons got ridges in TMP, to give them more of an alien appearance. Actually Unification treated the ridges as if they don't exist, otherwise Spock could have been recognized as Vulcan.
So I'd say that TNG treated the ridges as icing on the cake or to be more precise as crunching in the crisp.
That's a good point, and I do prefer the look of the bumpy headed Klingons to the fu-manchu type TOS klingons.