This is a proof that people do not like to login. Or they do not like to explicitly press the login button.
You can see that the yellow line is peaked at 5:00. That point is the number of guests who tried to post comments, but it failed though because they have to login before posting comments.
At 6:00 and 7:00, the comment box is hidden for ones who haven't logged in.
We can see that the red line is still the same. (The red line is the number of comments posted by members)
The conclusion is that when we force people to login before posting comments, they just leave!
