"When the righteous triumph, there is great glory, but when the wicked rise, men hide themselves"
This is a descriptive proverb that is designed to point out a phenomena which declares a truth. In other words, when you see people doing this type of thing, then somewhere in their lives this other thing is happening.
In the case of this proverb, the observable phenomena is people hiding themselves; feeling the need to protect themselves; to go away and not be seen. The cause this proverb declares is that wicked people are on the rise.
I have seen this in the church where all of a sudden a number of good people no longer want to attend a church. They feel the need to get away from what is happening at a church or from a person at the church. This means that there is a person or group who are pursuing a selfish, impulsive, or rebellious agenda in the church.
This would also be true for other organizations when employees want to leave or feel the need to document everything to protect themselves or refuse to be alone with certain people. Selfish, impulsive, and rebellious behavior is afoot.
Another view of this proverb would be that if you see the rise of wickedness in a church or company or civic organization, then you should protect yourself and in some form hide yourself. Do not proceed as the naive do and pay a heavy penalty.