That is very true. This org expects so much from people, that it's to the point where there's no excuse not to "progress," to keep up with the organization, othrwise you're viewed as being weak, or willingly grieving the holy spirit. So, to simply cope, and to avoid being harassed by the brothers, many claim to be depressed, sick, or rely on the "illness" of another family member as an excuse. It's a survival mechanism. My parents did it just to cope.
I've also seen it, though, when some actually develop depression, or a lower self esteem, due to always thinking that what they were doing was never enough. That was one thing my wife expressed. (This was especially true during assemblies and conventions - and can be very discouraging.) Sure the org tries to come across as understanding, by saying that everyone has their "limitations." For real? Thinking that I have "limitations" is supposed to make me feel better? If that doesn't make me think less of myself, I don't know what will...