>>214637200
This pissed a lot of people off, understandably so. It is tragic. But it's a fantastic ending, and it gets to the heart of who Sam is and why he does what he does, elevating him to one of the noblest fictional characters ever written.
Throughout all the series, Sam believes that "God, Time, or Whatever," is keeping him around from one person to another to make right what once went wrong. Then in the finale, he actually meets God, or a messenger, and learns that he himself has the power to choose his leaps. So he sacrifices his own happiness and desire to go home to save his friend and continue helping strangers across time. It's beautiful.