Why do you think it is that people experience boredom?

Because people can't find a thread to focus on (hey wait... I mean that seriously!). When one is surrounded by a couple of things and can only focus on them for a short period, and then the attention skips to the next and so on, and finally notices it starts all over again, then you have the really unpleasant form of boredom. Just to be tired, or unattentive, or defocused I wouldn't call being bored in the core sense. I'd say actually it is a kind of disgust. But darn... I can't go on here, because I'm waiting for Godot...

Spooky