While most religions popular in the Western world are concerned with traveling to a paradisiacal afterlife, there are those religions where reincarnation is a basic tenet. Rather than remaining in some other realm, the spirit of the person will return to the world of the living. How they return is a matter for interpretation for some, but others think they know due to the person’s behavior in their current life. Reincarnation does not promise a person will return in their current form.
The promise of paradise is often a way to modify bad behavior and keep a populace under control, but the duty for that does not sit with any religious or governing body within a faith where reincarnation is a part of the system. Each person is responsible for how their life is lived, and their good or bad behavior will control the type of being they are when they progress through death and into their next incarnation.
It might seem like a system that would not particularly work well with humans, but many raised within this type of system are ever vigilant to ensure they are not amassing bad karma. They know they can come back to a more difficult existence than the one they current have, so good behavior is their ticket to a better life after this one is done. They may not always succeed, but there is a system of atonement even in these religions that will help them.
Living for the next life after this one is a theme spread throughout many religions across the globe, and it seems the vast majority of people want to know there is more to life than what they are currently experiencing. For those who believe they will come back again, living for a better future is the goal they espouse to earn a better place in their next life.