But everyone experiences boredom differently, and for different reasons. I understand the OP because I don't get excited about things and live much of my life in boredom, I often pretend to be interested in things I think I should be interested in because, well, I may as well lay down and die if I don't, hoping that if I fake it enough it'll become genuine. But it never does. I just accept now that we live to live, everything I do will be for survival and avoidance of pain because I don't truly know if I'm capable of real, meaningful enjoyment. If I found something I enjoyed doing more than anything else in the world and could do it as a career, I'd still probably get bored eventually. My brain is just wired like that.
However some people's brains are wired differently, they can find hidden joys and fascinations in things a lot of us can't, and can stay excited for longer without the excitement being as taxing on their bodies as it is for some of us. For some people the feeling of interest or pleasure sticks more, unlike with some of us where it's forgotten as quickly as it was experienced.
I'm sure that there are far more people lying somewhere between the two extremes. I doubt there are many people who are bored in every career they go into, and I doubt there are many who never experience boredom.