This is my reason for burnout, opposite of your example. There's a thin balance doing more work because you enjoy, and doing it because managers are pushing you to do it. And now that I JUST do my job and what I'm asked to do, I have lost a lot of the drive that I loved about being a developer and engineer, making life kind of dull. Weird thing is that it is the job description that put me into this place, with no room for growth, and the search for new jobs has been dry, year after year of searching.
I traded my sanity for a big chunk of my life's enjoyment. That ain't great either.