If you cutoff a nigga's finger, he ain't going to bleed to death right then and there. Punch a guy in the face, he probably won't die unless you are wearing a metal gauntlet and punch him as hard as possible.
Now, if you escalate and start doing permanent damage and compounding injuries, that's different. Which is why torture should only be done by trained professionals who know how to keep their charges alive and capable of talking. One way to screw with the players who resort to torture is to have things go wrong outside of just killing the guy. For example, if you hit a guy in the mouth, now he can't talk correctly because you broke his jaw, so asking questions is now useless (and its possible he doesn't know how to write, or you already broke his hands so he can't write). Hit him in the head, and his memories become fuzzy and he has a hard time remembering the information. Stuff like that can screw over players who aren't actually intelligent about what they are doing, and just resort to torture for the sake of sadism.
Of course, if you are dealing with human opponents, torture is something that will inevitably come up when you take prisoners and need info. Especially during the medieval period that Dungeons and Dragons is ostensibly based on, since torture was commonly applied to elicit information and confessions of guilt during this period. And sometimes, if you have a target that can't be bluffed or simply intimidated into giving information, torture maybe a necessary last result. Off course, a relatively interesting way to screw with players is to simply employ the most obvious issue with torture and (one) of the reasons its no longer commonly employed: the person being tortured will simply tell their torturer whatever they want to hear make the pain stop, even if its a lie. So a person who breaks under torture isn't necessarily telling you the truth.
