I don't know, they just are. Personally I dry my hair thoroughly (having applied smoothing serum first) and then - ideally - section the hair and straighten each section at a time, although on a rushed morning it's usually drag it through the sides and ends at the back and that's it! LOL.
Perhaps it's something to do with the ceramic plates and heat up times, I really don't know but nothing else has the same effect. For me.
Oh and MM, I would NEVER spend more than I have to on ANYTHING.....they
were a Christmas gift though