1) Satan targets them because they do The Kingdom of God a lot of good and satan's a lot of damage.
2) Their goals, structures, settings, methods etc. are somewhat of a setup for strong striving people with unhealed personal junk multiplying and afflicting that on all at hand. I don't consider that the structures, goals or even many of the methods are that wrong--just that the people need more healing, deliverance, cleasnsing and monitoring on an ongoing, regular basis. Perhaps the whole organization does. I'll be sharing this with a Board member. I don't know what he'll do with it. He does care about such things.
3) The times we live in exacerbate all of the above.
4) Any Christian group seriously interested in doing great work for The Lord is likely to have similar problems. . . especially with performance oriented people.
I've found that performance oriented Christians have the hardest time understanding and allowing Grace to work in their lives. Particularly in the Bible Belt where you have religion and performance orientation mixed - what a recipe for dullness and legalism.