Defections certainly happen, but not at a rate that would be significant enough to overcome the fertility inside of the group. https://en.m.wikipedia.org/wiki/

Defections certainly happen, but not at a rate that would be significant enough to overcome the fertility inside of the group. https://en.m.wikipedia.org/wiki/Rumspringa https://en.m.wikipedia.org/wiki/Rumspringa Interestingly these communities have a mechanism for selecting out those who do not wish to comply or conform.