I don't get actually uploading those parses to fflogs, especially if they're incomplete/partial logs like in the case I saw.
There are people who are so parse-retarded they track everything.
You need to do so, in order to use
xivanalysis. Parsing is fucking pointless with casual content - you might be doing great but if your gear is below-par it'll reflect that- but figuring out what you're doing wrong is excellent. Normal raids and even alliance raids give you a lot of time to practice your basic rotation, before you worry about optimization shit. The tool is super useful to keep track of things that you're doing wrong, and even to let you know shit you were oblivious to.
Like I didn't realize that paradox-ice is something I'm supposed to be using regularly until I just looked. I used it in EW nonstandard for obvious reasons, but after it was removed I just got used to not pressing it. When it was added back in, I assumed it was just a movement tool. Since I was really only around to see how shit the patch content was, I didn't math out the potency to find that it's apparently worth pressing in each rotation, not just ones where you need the extra movement or an instant-GCD.
Obviously, the approach you can take when parsing (and not just looking to learn the basics) is very different. Like - you don't use triples for movement or xenos outside of burst phase unless you know you'll have them back up for the next burst / leyline, which means to uber-parse you have to autistically map out the fights and when you're going to expend every given resource based on your comp. This is really only possible because 14's design really isn't built around reaction so much as memorization, which is probably the wellspring of why there's so much fatigue with their entire encounter/job/rotation design atm.
Like it's cool on Shadow Demon to learn when to surecast around the square so you miss the first 2 knockbacks and then fall in line for the other 2, using a triple to keep pumping F4s all the while. On some level you have to remember when you're good to drop your leyline and maximize time in it. But man is it boring to go "yeah, bank all 3 glossies, don't use any triples, because at the end of this phase you'll have the time to dump all of it."