There are a few reasons in my opinion that lead to this ,
The information age it is, wikipedia is filled in by us and so we're the people with the knowledge.. Okay, but stick to what you know and you're sure of.
- Listening to others speak and taking their words as your source of information. This is common along jobless corners, at the stage, in a mat or at a local.
- Looking at pictures in a newspaper. Barely reading the stories or sometimes reading newspapers and adopting a writers point of view in a subject.
- Ego cause you think that since you're an authority else where then you are everywhere else.
- And lastly guesswork. You just wanna flow with the conversation/debate and so you keep putting your 2cents.