Well, a broken penis can hurt as hell. And if you always have extreme pain because the ligaments don't want to stretch as much as needed anymore it will also hurt like hell.
I have read about a guy eho was chaste in a cage without erection for several years. Had to go through a cortisone therapy and lots of stuff because he had that issues. He felt it was better to have it removed than going through the surgeries. I don't know him personally but he was a verified member and I also have read a lot about male chastity for myself ... and also found two urologists who confirmed me that something like that can happen and that it's very painful. Some others don't want to talk about stuff like that because they have never heard about a similar cases where someone was locked in chastity for years... I'm not a doc myself, so I can't approve anything ... just read ver, bad things from people who say to be locked for years without errectipn and some experts
I personally met someone once ... don't have too much contact with him ... who says to be locked for a year without problems now - but honestly don't knoe if it's without cleankng lockups for occasional erections.