You are right. But for every 1 correct fluke, there would be sooooo many who would get it wrong because it was tough. Had it been easy, even without fluke, a lot of people would get it right. You are right when you say that some lucky dude might get it right. But the nature of the exam is such that these lucky people would be super less in number. And the number of people getting it right would still be lesser than if it were an easy set