When, how, and why did the Moravians stop praying 24-7?

When I went to Israel a woman told me about this movement of the 100 year prayer. She then proceeded to tell me about the first wife of a leader of the movement, whose name I don't know. She supported what God did in people's hearts and thus many missionaries went out into all the world and impacted it. The first wife died and the leader took another one. The second wife had areas in her life she didn't work through with God. This caused her to be jealous and she started manipulating the intercessors hearts. When people felt called into ministry she was there to state, that it was unnecessary. She encouraged the stopping of going out into the world. So many didn't go. I don't think that everyone just listened to her, but as the wife of the leader she had influence and she used it to sabotage the work of God and to sow discord. Thus the prayerchain stopped eventually (so I was told).

If I don't work on my heart becoming whole by seeking God in the secret and knowing and trusting his truth and love, my heart will be hardened by various things such as fear, jealousy or bitterness. If my heart is separated from God's, I won't partner with him, but pursue different things than he does. I might actually ruin the work that the spirit is doing by getting in the way. He asks us not to do that.

I learned a little bit about this in the seminary I attended, so I have a somewhat (incredibly, actually) vague idea.

When: Correct assumption that it would have stopped in 1872. There are no recorded instances of “when” it stopped, at least none I learned about or could find online. Some people, in fact, dispute whether it actually ended or not - certainly possibly some Moravians still exist today, carrying out this prayer. In fact, if you look it up a little more, some believe the movement lasted over 125 years.

How: Nobody really knows how it stopped. Assuming though, at least in the seminary where I learned about it, the death of Count Zinzendorf is often considered to be a factor to an eventual decline. The Moravian Church is still very much alive today, but not many know whether this practice is still carried out by the church as a whole or by separate members, as mentioned above.

Why: Nobody really knows why, either. Again, it’s believed Zinzendorf’s death is considered one of many factors. The coming 1800s brought the Napoleonic War, which very well could have contributed to it, as well as the French Revolution. My teacher thought, for the most part, the Unification of Germany was possibly the biggest factor.

The issue in determining a proper answer to this question is that this community at the time was very small, having 76 homes in 1777, and much of what went on there was within the community, and not publicized in many other places to our knowledge.

From a Moravian website in the UK:

The industrial revolution and 1870 Education Act brought changes to the settlement' way of life and the sisters' house and schools were closed in the latter half of the 19th century. The additional buildings were then converted into dwelling houses which are managed by the Unitas Estates Company. http://www.moravian.org.uk/index.php/uk-congregations-list-for-the-moravian-church/yorkshire-district/gomersal

Its only referring to the closing of a church school connected with one congregation, but it is most likely also involved in the general downturn. After all, the inability to keep religious schools running, and their replacement by a secular school system, can very easily make a big dent in a minority denomination's numbers.

Looking up the Elementary Education Act 1870 we find on Wikipedia:

There were ongoing political clashes between the vested interests of Church, private schools and the National Education League followers. In some districts the creation of boards was delayed by local vote. In others, church leaders managed to be voted onto boards and restrict the building of board schools, or divert the school rate funds into church schools.

The vested church interests referred to there are of the Anglican church, not the Moravians. Losing their own schools and having to send their children to secular or Anglican schools, either one, would undoubtedly have been of great consequence to the denomination's future.

Although divided by an ocean, this article about Bethlehem Pennsylvania seems to tell the same basic story:

Since 1741, Bethlehem has beckoned travelers to experience the warmth and hospitality of this delightful community. In that year, a small group of Moravians settled on the banks of the Lehigh River near the Monocacy Creek.....

On Christmas Eve of that first year, 1741, the Moravians' patron, Count Nicholas Ludwig von Zinzendorf of Saxony, Germany, visited the new settlement. In their two-room log home that housed both man and beast, the Count christened the community "Bethlehem"....

With the advent of the Industrial Revolution, Bethlehem became a center of heavy industry and trade....making the city a "melting pot" of cultures, blending one into the other. http://www.bethlehem-pa.gov/about/history/

And again with LITITZ, PA:

Lititz was established in 1756 by the Moravian Church as an exclusive religious community until 1855, when the town welcomed people of all religious creeds. The town played an active role in the Revolutionary War, Civil War, and industrial revolution, and served as an early musical, educational, and commercial hub. http://www.moravianmanor.org/lititz.htm

Or again :

The cottage industries of the Moravian Settlement were eventually overtaken by the Industrial Revolution and members sought work and business outside the settlement. http://www.derbytelegraph.co.uk/Hidden-past-village-founded-pioneering/story-16865225-detail/story.html#ixzz37ELK0udO

Who has time for 24/7 prayer when you've got to commute?