When I retire, I'm going to... 
Philosophical Engineering
Answering this question when I'm not even 30 years old, might lose me credibility if I suggest retirement is a poor life decision to work towards in life. What I don't understand about this societal construct, is that this "peak potential" of mine has to be calculated to some arbitrary age in my 60s. And yet when my dad turned 50 the joke was that he was on the "other side of the hill" already. 
Our peak potential should not be measured by some arbitrary age to allows us to look back and say what a great life I lived. Clearly not being 65 today, I can't justify what I would say. But, having grown up in New Hampshire and learning to hike actual mountains and reach the peaks, I learned that regardless of the way you hike or climb, your physical build, your mental toughness, we can all make the climb to the top. 
So am I at the "top" in my life? I'm not sure how to even answer that because when I was at the top of a mountain back in New Hampshire, I didn't see any signs saying my life was at it's peak potential. There was no trophy handed to me when I reached the summit, and there wasn't any finish line because I realized I had to also climb back down! Rather when I got to the top of the mountain, there were two things I gained. 1) the potential of the views being spectacular and 2) it took hard work to get there (posting memes does not count).
Since it was cool to be on top of a mountain back in New Hampshire, why not take the two things I gained and work hard for the potential of spectacular views (and no, this doesn't have to mean sitting on a beach doing nothing). 

Which mountain are you climbing in life?