They are just trying to protect the REST of us from...
Muslims (Mohammed was God's LAST Prophet: PBUH)
Mormons (Brigham is His Prophet)
JWs (Prophet? Who needs a prophet when you've got a FINE organization like the Watchtower?)
Scientologists (Yo momma HOLLERED too loud when you wuz born! We gonna deprogram you! Give us money!)
Christians are, in general, all over the place concerning new revelations. Moslems, though, are adamant ~ there are none.