Cheating can happen in a lot of different ways. When people cheat, it's not fair to other people, like the kids who studied for the test or who were the true winners of a game.
Many people like the action of cheating. It makes difficult things seem easy, like getting all the right answers on the test. But it doesn't solve the problem of not knowing the material and it won't help on the next test—unless the person cheats again.
Some people lose respect for cheaters and think less of them. The cheaters themselves may feel bad because they know they are not really getting that good grade. And, if they get caught cheating, they will be in difficulty at school, and maybe at home, too.
Some kids cheat because they are busy or lazy and they want to get good grades without spending the time studying. Other kids might feel like they can't pass the test without cheating. Even when there seems to be a "good reason" for cheating, cheating isn't a good idea.
If you were sick or upset about. something the night before and couldn't study, it would be better to talk with the teacher about this. And if you don't have enough time to study for a test because of swim practice, you need to talk with your parents about how to deal with swimming and school.
A kid who thinks cheating is the only way to pass a test needs to talk with the teacher and his or her parents so that they can solve the problem together Talking about these problems and working them out will help kids feel better than cheating.