The adjective eventual is used to describe something that is likely to happen in the indefinite future. If you are a teen, you can't wait for your eventual graduation from high school, but later, you'll look back fondly on those same high school days.
Eventual implies that the result will occur due to circumstances already set in motion or if a given set of circumstances happens. In other words, eventual is not used to randomly predict the future. You may hope to win the lottery in the future, but you can't talk about your eventual lottery win because you have no way to guarantee your numbers will be chosen — unless you've figured out a way to rig the system. If you have, maybe you should think about your eventual jail time.