This doesn't know the important part. Will I live to 62 as the earliest of my ancestors died, or 98 as the latest? My family history is about average for lifespan but that is a big difference. If I live to 62 I should retire at 50 - or perhaps I shouldn't have bothered saving at all since the growth isn't there. Of medical advances make me love to 150 I should save until I'm 80 which will be a nice income to really enjoy the rest of my life.
I want more defined benefit accounts, but they are hard to find
That's in the full planner, just not the Quick Check. Horizons are sampled per person from actuarial mortality tables, so you get a distribution of lifespans rather than one guessed end age. You can also pin a fixed age and run your 62 and your 98 separately, which given that spread is probably worth doing.
So the thing is that no one knows that part.