I guess I'm not sure of the direction here. Do you mean because they just don't play well or because they check out.
My son so looked forward to his senior year. It turned out to be a disaster. Statistically at the plate the worst of his HS career by far. He made excuses (only one really) and I blew them off. I told him he was just pressing and trying to hard. He was up for state player of the year and also being looked at for the draft. I was sure it was just a matter of him relaxing and playing his game. Never happened.
On the mound was a different story. He was basically unhittable. That provided a little hope. Looking at the playoffs if the team just took care of business and we made it to semi-state I figured he'd be hard to beat and a state title would take a little sting out of the way the year went. The game before playoffs he tore a muscle in his bicep and that was that. Just a crap year.
Now as to his excuse. He wanted to use his Baum bat but the HS coach said no. Putting himself before the team he said. So I found him a end loaded 34" LS on JustBats for $99. When the bat arrived we weighed it (like we always do) and it was 33 oz. He voiced his doubts he could swing it and I was like "BS, it's only HS pitching and your a strong kid". Was it the bat, IDK. After the season he told me he just couldn't control the bat through the zone or react to pitches. He told me that throughout the year and I blew him off. He played four tournaments that summer on a team full of collage players, a requirement to be on the team. Played pretty high level tournaments. Used his Baum, and was his old self. He raked, just absolutely raked. One week after he couldn't hit a baseball to save his life you couldn't get a ball past him.
The one good thing about the year was, I always worried whether the kid really loved baseball or loved being a "star" while playing baseball. Through it all he never wavered in his desire to play. Never once was he like "I don't need this".