1 roughly means that when someone does something, everyone is watching, but they almost agree, or laugh at others. Some people don't admit that they have done something wrong, and another says, "The eyes of the masses are discerning."

The so-called "the eyes of the masses are discerning" is just a slogan without any logical basis. One person will make mistakes, and so will a group of people. Then do we have any evidence that a group of people will make fewer mistakes than one person? I can't. On the other hand, when a person is alone, he can only rely on his own judgment, so he can always keep calm.