Why pursue the development of rejuvenation therapies? What do I get out of it? The answer to that question - health! - is self-evident to those of us who have been thinking about this for a while, but a fair amount of advocacy for any cause is a matter of explaining what is obvious to the advocate, but not to someone unfamiliar with the idea. Sometimes it is hard to see one's own blind spots, and especially so when it comes to long exposure to a subject: we forget what it was like not to know. Given that, I think an overview of the point of developing rejuvenation therapies, discussing what an individual stands to gain, is a good thing to have in the toolkit.
I'm sure you've noticed that the Life Extension Advocacy Foundation has been shouting from the rooftops for quite a while that rejuvenation biotechnologies need to happen, and we're doing our best to make them happen as soon as possible. The job isn't easy; the fact that numerous people still raise concerns about the idea doesn't make it any easier, and we invest part of our time duly addressing those concerns. But the discussion about what might go wrong or how to prevent this or that hypothetical problem might draw attention away from another, possibly even more important question: why do we strive to make rejuvenation a reality? There's not much point in doing something if it yields no benefits, especially if that something requires as much hard work as this cause does; so, what are the expected benefits of rejuvenation?
Health: rejuvenation, we have said time and again, is pretty much all about health. The causal link between biological aging and pathologies is well established, and even when we account for the few elderly who are exceptionally healthy for their age, we're left with the obvious fact that the older you are, the sicker you are - and even the aforementioned exceptions aren't in the best of shape. To the best of my knowledge, the number of people who actively wish to be sick at some point tends to be fairly small; so, when you think that a truly comprehensive rejuvenation platform would allow people to maintain youthful health irrespective of their age, the health benefits of rejuvenation become crystal clear.
Independence: frailty, failing senses, weakness, and diseases aren't good friends of independence, but they are good friends of old age. That's why nursing homes exist in the first place - to take care of elderly people who are no longer independent. Again, even the few exceptional cases who manage on their own until death don't have it easy. Having people doing things for you can be nice in small doses, but having to have people doing things for you, not so much. Rejuvenation would eliminate the health issues that make the elderly dependent on others.
Longevity: as odd as it may sound, longevity is really just a 'side effect' of health, because you can't be healthy and dead. The longer you're healthy enough to be alive, the longer you'll live. Since rejuvenation would keep you in a state of youthful health, the obvious consequence is that you'd live longer. How much longer exactly is hard to say, but as long as you're healthy enough to enjoy life, it's safe to say that longevity would be a benefit; you'd have more time and energy to dedicate to what you love doing, and you could keep learning and growing as a person for an indefinitely long time.
Ultimately, all of these perks can be summarised into one: choice. If we had fully working rejuvenation therapies available and were thus able to keep ourselves always perfectly healthy, regardless of our age, we could choose whether we wanted to use these therapies or not. Those who wish a longer, healthier life could avail themselves of the opportunity and escape aging for as long as they wanted; those who prefer to age and bow out the traditional way could just as easily not use the therapies. Rejuvenation would give us an extra option we currently don't have; everyone is forced to face the burden of aging and eventually die of it, for the moment. Being able to choose what we wish for ourselves is one of the most fundamental human rights and an obvious, unquestionable benefit.