Or somebody is wrong on the Internet.
This past week I came across a site with a ton of comments which turned out to be pretty much just an argument between two or three people. I was struck by one authoritative commenter insisting, "I'm right on this!" Back and forth, back and forth the comments totaled up. Why would anyone do that? If you believe you are right - state your case and move on.
We all want to be right - and when we are convinced we are right, we often refuse to listen to those who contradict us or just want us to consider their plight from another point of view - especially concerning topics about which we either know very little or find baffling.