If their blind that means that they can't see where the other people are and where to shoot at. If that person is deaf then they can’t hear their commander, and can’t hear the shooting behind them. They could become blind if their shot a way to make them blind. They could also become deaf if the sound bursts their eardrums. That's the final reason why mandatory military service is cruel.
Mandatory military service means that once you hit a certain age you start training for the military and serve for your country if you like it or not. Mandatory military service is cruel and uncalled for because they could have a medical issue, missing limbs and body parts, and they are blind and deaf. The reasons they do that is because their third world countries that don't have a lot of people wanting to join the military so they make it mandatory for everyone. Not all countries are like