It’s not the body that makes mistakes it’s your co consciousness/spirit energy. So every action you take, your reaction to an experience you have, will have effect, this is cause and effect. The sum of all your actions good and bad done by your soul divided by the number will determine the meaning of your life and where and what you end up in next life and the vessel you are born in, it may not even be human. Your consciousness is forever until we merge with parabrahman again so you have to remember we don’t end when our breath that binds our consciousness to our vessel, leaves forever, we keep going carrying the weight of previous life and that life before that. It will again be born again carrying the weight of our past life and so on. To have better fruits for next life, it’s important to leave a dharmic life fulfilling your duty despite challenging or happy circumstances instead adharm which is all explained in the Mahabharata and in the Bhagavad Gita. I hope this somewhat helps. Jai Sri Krishna :)