
Originally Posted by
Risvertasashi
There is a level of inaccuracy/estimation and simulation involved, but they're pretty transparent about exactly how they make their calculations, and as far as rankings go, well, everyone gets the same approximations. if you want to compare, go hit the SSS dummy and look at the numbers the game reports as your DPS and compare to FF logs or whatever. It should be very close, but not perfectly matching.
Now, as for your personal rankings, there's a lot that goes into it and isn't necessarily within your control. For example, having a food buff up and using potions has a substantial impact, even if all other elements are perfect or close enough. And right now people aren't highly geared, so gear differences have a big impact as well. And then if you're not in a party that provides raid buffs, or people can't keep their windows aligned, that'll be another hit to ranking.
If you really want to know, throw up your logs somewhere and ask for feedback and people can identify specific things that may be an issue - whether or not that's your rotation. (Also, be careful getting your advice from The Balance, they're ok for getting to a baseline but somewhat often make suggestions that are actually terrible for optimizing your DPS in the high end).