I think people get bored by many things: monotony, lack of variety, routine, etc.

I usually get bored when I have to constantly repeat the same activity and besides this activity doesn’t give me a profit. So, working in front of a computer is not boring. It is boring if I only work in Excel or do document templates in word. I get bored when I have to give classes to kids who don’t want to learn. Well, I get bored but I get mad too.