What is parsing?

[Risvertasashi]

I wonder what made parsing so popular in FFXIV. Surely lack of dps meters is to avoid bullying and gameplay compelling. And the increase demand in popularity is a result to off-FFXIV gamers such as WoW gamer's habits leaking into FFXIV? I hope not.
I understand the need for it, I am just concerned with the toxicity that gets generated from it :/

FF14 has a lot of strict and difficult-to-meet DPS checks. In high end content, failing to meet the DPS check is one of the most common failure points, especially with pug/PF parties.

And it's relatively obvious when other mechanics fail - like if someone didn't stack for the stack marker, or a DPS ate a tankbuster, well, it's pretty obvious from the sudden loss of health and life.

When the boss enrages you know there isn't enough DPS. But if people are just good enough at their rotation to look competent, it isn't obvious exactly where the problem is unless you turn to third party tools. (And if someone just wants to know if they're doing their rotation right so they're not bringing down a group, that also isn't really discernable via the tools and feedback mechanisms available in game)