We all get old. It's not something that people like to think about, but dammit we can't hide from it. People get old and they die because that's the just cruel game we inadvertently signed up for when we were born. All we can hope for is that once we're gone, we've left behind a legacy that will carry on our memories for quite some time. And since actors are people too (kind of), it's reasonable for them to start considering their own legacies once they realise they might have more years in the rearview than on the road in front of them. This holds doubly true for actors who are known for portraying legendary characters. That's the impetus behind most of the "passing of the torch" moments we've witnessed in modern cinema, where an older actor hands the reigns of an iconic character (or an entire genre, as the case may be) over to a younger actor for a remake or a continuation of a franchise. Sometimes they're awkward. Sometimes they're touching. But it's always nice for the audience to get some sort of closure from the old guys and feel like it's okay to watch this new version of something we still love.