Recidivism means when someone who has done something wrong in the past, like breaking the law or committing a crime, does the same thing again. It's like when you get in trouble for doing something wrong, like taking cookies without asking, and even though your parents tell you not to do it again, you still do it the next day. That's kind of like recidivism, but with bigger and more serious things.
Sometimes people who do something wrong and get caught by the police or go to jail, might get released and be allowed to live in the community again. The hope is that they learned from their mistake and will not do it again. But sometimes, they will repeat the same mistake or something similar, and end up back in jail or prison.
When this happens, it's called recidivism. It's a way to measure how many people who have been in trouble with the law before, end up back in trouble again. One big problem with recidivism is that it can be very expensive to keep putting people in jail, over and over again. It's also not good for the person who is doing the same wrong thing again and again, as it could mean they have not been helped to change their behavior or given a second chance to live a better life.
Overall, recidivism is something we want to try and prevent, by helping people who have done something wrong to learn from their mistake and not repeat it again.