Humans are very intelligent animals and we need quite a lot of mental and physical stimulation. Our capacity for learning is pretty massive and if we continue to do the same things over and over again we get bored.
Our brains are incredibly complicated machines!! If they have to do the same task, or something that they aren’t connecting to, they come up with better things to do… why we weren’t wired to have laser focus all the time, I don’t know! Your eyes even can get “bored”–that’s what causes the cool optical illusion of spots and wavy lines with you look at really close series of lines for too long.
Because they don’t know what to do with themselves. I think that’s a problem of our modern times – a few thousand years ago humans had to focus on surviving and bringing up their children only. They had to look for or hunt food, make sure they are not killed by enemies or wild animals and make tools, clothes, huts etc to be protected. I don’t think these humans did know what ‘being bored’ means. Nowadays everything is a lot easier, for food you just go to the supermarket (if you have money) and for almost everything else too. So there is a lot of time left, which you can spend for whatever you want – and some people don’t know what to do then – so they get bored …
I know that I get bored if I’m doing something repetitve, or if I don’t have anything to do. That’s why I try to fill my weekends up with lots of fun things otherwise I wouldn’t know what to do with myself!