"Because I could not stop for Death-"

"He kindly stopped for me-" Have any of you every read that poem by Emily Dickinson? I encountered it last year in my AP English class. In fact, I had to write a paper on that poem.

While reading the chapter, I came across something called the four stages of the proper life. The fourth one was of most interest. It is called sannyasa, which is when one leaves his or her family to prepare for death. It is such a different concept than the poem of Emily Dickinson. In the poem, and from what I gather about life, we do not slow down for death. Yes, we may worry about our death which can happen at any moment, but it doesn't really slow us down. In Hinduism, however, people abandon their families to prepare for death. I guess it might be their way to salvation, which is what they strive for their whole life. But, to actually prepare oneself for their death? It's crazy!!

Question: Why is it that Hindus can just prepare themselves for death? It would seem like a topic you would not want to prepare for, that you would rather just happen.