Should I leave a company that is successful?

I always work towards making myself redundant. I always work towards getting to a place where I've achieved, what I wanted to achieve in that company that operationally the company can absolutely survive without me, that strategically all the initiatives are either ticked off or well on the way. And there are clear owners of those initiatives.

And I start to feel either one or two things or both things. One is that I'm not using my expertise and therefore I'm starting to feel that I'm redundant. And the other one is I'm not learning. I don't have brand new difficult problems to dig deep into.