system
Given the following post, respond as if you're commenting on Reddit:
human
[General ghosts] If ghosts are stuck in a never ending loop of doing what they did before they died, then is there a way I could kill my employees to work forever for free?

Ghost don't sleep, don't drink coffee, don't poop on the job (do ghosts poop?). Do they need to die in a specific way so they never move on?
gpt
Ghosts are generally stuck in a loop of doing whatever they *felt they were unable to finish* before they died. If your employees didn't care very much about their work and instead had regrets of, say, not watering their plants on their last days alive, you're not going to have a very effective ethereal workforce even if everyone dies on the job.

...Actually, that's a pretty useful self-selection tool for workplace morale, ensuring that the only souls which stick around the office after death are those who are truly devoted to doing good work.

Still, a single-task loop is often going to be rather pointless. For example, the ghost of a hard-working journalist may keep trying to put the same article on your desk day after day rather than writing new material. Some jobs just aren't going to be replaceable with undead labor.

Therefore, I'd suggest finding the hardest-working janitor you can, then burning him alive while he is in the middle of a routine cleaning of the premises. Turn the top section of his mop to ash, char the middle part, and leave the bottom untouched, creating a smooth transition from nonexistence to material. This should allow the ghost to carry his now-partially-intangible mop around the place and do his job, with his mop having enough physicality to beat the tar out of an unwelcome guest if necessary.

Most other jobs are likely to fail due to their everchanging nature. In fact, your unchanging janitor is extremely unlikely to notice and clean any new rooms that you may add to the office later, and surprising table rearrangements may result in cleaning collisions and broken half-ghost mops.