Sometimes it could be physical injury too. Last year, when my son was playing short stop, he jammed his left thumb when trying to tag a runner on 2B. He thought the left thumb shouldn't matter to batting, so didn't tell the coach and continued to play. In the next few weeks, we just saw his batting stats fell dramatically. His swing was just a little bit slower and just a tiny bit less powerful, but that's enough for a lot of outs. Once his thumb cured, his batting was back to normal. I'm not sure if the coach noticed it or not, but his stats at beginning of season and at end of season were both great; there was just a black hole in the middle for a few weeks. He didn't tell anyone about the injury, so coach and other player probably thought he had a slump. I'm happy nobody offered suggestions to change his swing mechanics.
Question to the forum: in this situation, should he tell coach and get benched? Or continue to play but let stats drop?