Well they don’t make it easy.
In boot camp, there was only 1 recruit in my platoon that actually got washed out. He basically sat down on the floor one day and refused to do anything. Got yelled at, threatened, to no avail. They had MPs come and take him away. No idea what happened to him.
In boot camp, if you fail a phase such as the range, you get ‘dropped’ back to a training company that is in training phase behind you. We had a pair of twin brothers dropped to us because they both failed to qualify on the range. When we went, they failed again. I believe that they were intentionally failing to try to get out. With all of the instruction, it’s damn near impossible to UNQ twice in a row. Not sure what happened with them.
In boot camp if you are injured and unable to train, you don’t get to leave unless it’s a really serious injury. Instead, you get sent to MRP, the Medical Rehabilitation Platoon, where from what I understand you go to your physical therapy and appointments and get assigned to working parties. Some guys spend, literally, months there. Once you’re fixed up, you drop to a training company at the phase you were removed from you original one.
If your body composition or physical fitness are questionable, you are sent to PCP, Physical Conditioning Platoon. At PCP you basically PT all day long until you pass the physical fitness test, and likewise are put back at a training company.
At SOI, we had at least 2 dudes who got out because they were ‘suicidal’. I don’t know if they were or not, but basically you CAN fake it until you make it with that one. They got out before SOI was over. I spent several days sitting in the rec room watching them.
Once you get to the fleet it’s possible to get out for injuries if that’s the direction you’re leaning. I can think of at least 3 in my company that I think probably milked recoverable injuries to a discharge. Heck, I had an ankle injury once and the Navy doctor straight up asked me if I wanted to be discharged.
Then there was one guy who got discharged for being suicidal. I actually believe that was the case with him. At one point he was standing in his window on the 4th floor off the barracks…sooooo. He was a troubled dude. Guy didn’t look in shape at all, but one day he got a perfect score on the run portion of the PFT, 3 miles in 18:00. I asked someone wtf, and they said he just went out and ran all night, every night. I still remember him waving from the back of a USO van on his way off base for the last time.
And then of course, you can wash out by doing something to get dishonorably discharged, like dealing drugs. Which happened to a few guys in the 2nd platoon of my company. Several ended up in Leavenworth. Thereon, that platoon was known as “dimebag deuce”.
ETA: also had one guy in our company get discharged because he intentionally kept gaining weight.