Out of fear, I nagged my now eighteen-year-old son too much when he was a boy. Because he's autistic, I worried so much about him and wanted him to be like the other kids, blend in with the crowd, and not look and behave differently from his peers. I hated when he'd “stim” because everyone would stop and stare (or, at least, it felt that way to me). When I came to terms with my own anxiety and self-consciousness about his autism, I was able to back off from the nagging. It wasn't working, and it was hurting our relationship. I let go of my immediate desires (having him clean his room, having him get decent grades) and started looking at my long-term goal (rearing a son who'd become a strong, kind, and independent man one day). My son just graduated from high school and will start college in the fall. I'm so glad I stopped the nagging and built a beautiful relationship with him.
Having charts and a reward system worked well with my son. I never nagged but gave him points on his chart when he completed a task: doing his homework, cleaning his room, taking out the garbage, walking the dog. After a certain number of points earned, he got a reward that we had previously agreed upon: a bowling night, going to the movies with a buddy, having a sleepover, spending a day at the beach. If his tasks went undone, there were consequences on the weekend: no video games, no trip to the skate park, no going over to his friend's house. I stayed firm, consistent, and unemotional. When he saw that I meant business, he began to get things done and enjoyed earning his perks. He felt in control, and it built his self-confidence. So I recommend that you stop the chasing and let your child live with the consequences of his actions.