2. Very few people even take it
Only sommeliers who have previously passed the Intro, Certified, and Advanced Sommelier exams are invited to take the Master Sommelier test. And only Master Sommeliers can gain membership to the Court, which knocks out holders of their similar-sounding but purely theoretical (and easier, sorry guys) Master of Wine diploma.
3. It’s a trifecta of difficult
There are three components to the Master Sommelier test -- theory, service, and blind tasting. Acing all in one sitting is practically unheard of.