However, it usually did end exactly that way. Here's Gamaliel In Acts 5, comparing Jesus' disciples with other movements (my bold):Even Jesus couldn't convince everyone, that's why they nailed him to the cross. But something happened shortly afterward which is why the biggest church in the world is located in the heart of the Roman Empire (Rome) and why we are discussing all of this 2000 years later. All of this should have ended with a bunch of scared apostles scattering never to be heard of again, but something happened, and it didn't end that way.
And there have been innumerable less famous groups of disciples which have disappeared as soon as their master is slain. The Jesus movement is an exception. It had strong enough delusions, or an impressive enough ideology, to survive. (Or Paul saved it by making a diluted version of its message palatable to pagans and semi-judaising "god fearers".)35 And said unto them, Ye men of Israel, take heed to yourselves what ye intend to do as touching these men. 36 For before these days rose up Theudas, boasting himself to be somebody; to whom a number of men, about four hundred, joined themselves: who was slain; and all, as many as obeyed him, were scattered, and brought to nought. 37 After this man rose up Judas of Galilee in the days of the taxing, and drew away much people after him: he also perished; and all, even as many as obeyed him, were dispersed. 38 And now I say unto you, Refrain from these men, and let them alone: for if this counsel or this work be of men, it will come to nought: 39 But if it be of God, ye cannot overthrow it; lest haply ye be found even to fight against God.
But that doesn't prove it enjoyed divine protection. How many crazed preachers were active in the United States around the time of Joseph Smith? Very many. His Mormon outfit survived, while almost all the others evaporated. Does that mean that the Book of Mormon is the word of God? No way!