[majormajor]

> e.g. By definition the 99.9th percentile person cannot live a 99.999th percentile life, if they did they would in fact be that amazing.

This seems far too deterministic and I think is contrary to what you're replying to.

It sounds more like a 99.999th percentile person[0] that constantly reaches too far too early, before being prepared, will not have a 99.999th percentile life. A 99th percentile person who, on the other hand, does not constantly fail due to over-reach, can easily end up accomplishing more. (And there are many other things that might hold them back too - they might get hit by a car while crossing the street.)

[0] in whatever measurement of "capability" you have in mind

[MichaelZuo]

Well the critical thing is that we can’t determine who is at what percentile until after the fact. So for example an early bloomer genius type, who is 99.999th percentile among everyone in the same birth year cohort, could suddenly crash back down towards the average.

There’s no practical way to determine that looking forwards in time.