The Evolution Cycle from Sect to Denomination
When the sect leader dies (as they inevitably do) the sect will either fall apart and disband or evolve into a Denomination, according to the sociologist Niebuhr. A good example of this would be Methodism. Originally a breakaway sect from the Church of England, when the sect leaders died the sect evoloved into the Methodist denomination it is today.
Some sects, like Methodism, can easily evolve into denominations as their main task is to convert people to Christianity. This can be more easily performed as a conventional denomination rather than as a move deviant sect.
Other sects, like Jehovah Witnesses and Seventh Day Adventists, do want to convert but they need to keep separate from the sinful world, so need to stay as a sect to avoid 'contamination'.
Other established sects, like the Amish will always stay as sects as they are already separate from the world and have no wish to convert people.
Other more deviant sects, like Haven's Gate, Aum and Jonestown don't evolve.