If you have a chance to make things better where you are, then it’s good for everybody who works there. Also, you might not even have the option of getting a job elsewhere depending on where you live and what qualifications you have.

I've changed the place I work immensely in my three years here, and I think for the better. But at no point did I (or would I) threaten to leave if they didn't change... It just wouldn't work.

if it was a bad place for other people to work at.