The evidence suggests that Jehovah's Witnesses have a very high rate of depression and mental illness. They are kept in fear of the world, Armageddon and demons. They are also kept very busy. Consider a common schedule for a Jehovah's Witness who is a father, but doesn't have a position of responsibility in his congregation.
A typical day of work. He comes home tired, but has to study for the book study the following evening.
A typical day of work. He comes home tired, but has to shower and get ready for the book study. He helps his wife get the kids ready. He may not have enough time to eat a proper supper.
A typical day of work. He comes home tired, but has to study for the Thursday night meeting. He doesn't have to prepare a talk this week, so he gets to "relax" a little bit.
A stressful day of work. He has to work late and and doesn't have time to eat before going to the two hour meeting that night.
A typical day of work. He comes home tired, but looks forward to the weekend. He knows he should help his children prepare a presentation for the door to door ministry and prepare one for himself. He watches TV instead and feels a little bit guilty.
A day off. He helps his wife get the children ready for a morning in the door to door ministry. He tries to help his children work up a presentation between doors. He just wings it at his doors. Afterwards, he gets caught up with work around the house. The children play by themselves.
Another day off. He helps his family get ready for another two hour meeting in the morning. Afterwards, he is tired and watches TV with his family and dreads the start of the next workweek. That night, a couple of elders come by for an "encouraging" shepherding call. They are concerned about him and his family. He admits that he has had a hard time conducting a regular family study and realises that he forgot to do that this week. He also admits to being behind in his personal study and his reading of the magazines and books they receive on a regular basis. The elders talk to him about the serious responsibility he has as the spiritual head of his family and read this scripture at 1 Timothy 5:8, "Certainly if anyone does not provide for those who are his own, and especially for those who are members of his household, he has disowned the faith and is worse than a person without faith." (New World Translation)
This is just a regular publisher. If he was an elder he would be far busier with preparing talks, attending elders meetings, doing paperwork, going on shepherding calls, getting late night calls from troubled congregation members and so forth. Jehovah's Witnesses can never do enough and are often depressed about their failures. This makes them much more vulnerable to mind control techniques that depend on fear, guilt and fatigue.