My clippers lie.
I use them without guards to shave my head, and to also thin my beard and on occasions, my eyebrows (bushy eyebrows are a family trait - in the men, anyway).
However, the word thin does not accurately describe the process. A more accurate description would be "yank out with as much force and as little mercy as possible" because this is what happens.
To be fair, a set of slippers with the words "trim" and "yank out with as much force and as little mercy as possible" would be about a foot wide, and just not feasible - so I suppose that "trim" will have to stay.
But believe me, they do not thin. They rip.