Labor is when you do a thing that has value to society.
Work is like, a job, where you do labor (or not) and that pays you so that you can spend money to sustain your existence. If you get disabled you can be fired and not have money long term to continue existing.
People, ironically enough, are more efficient laborers when they aren't doing it in the trappings of work, so there isn't any reason for work to exist.