Things to think about before you call someone "Bad"

[Legion88]

Things to think about before you call someone "Bad"

Before coming to your points it is important to make sure we are talking about the same topic.

1.) I don't call someone "Bad", i don't get personal and damn the person.

2.) I call their playstyle "Bad" or harmful for the party or their understanding of job and content mechanics deficient or "Bad".

3.) I don't judge by high standards.
For content mechanics it should be basic to know that orange stuff is harmfull and should be avoided, also the stack marker (circle with arrows pointing inside) is a universal marker not changing in its effect and huge mob packs should be burned with AoE.
For job mechanics i don't need optimization, just the basic knowledge dependent on their level.
In general the upkeep of upkeep mechanics like Heavy Thrust or Straight Shot also for job specific basic mechanics like for BLM the circling of AF and UI, for higher levels the use of Enochian and enochian based skills, for BRD the use of it's DoTs and songs, for tanks to switch between tank and off stance reasonable, for healer to DPS in healing downtimes just as examples.

So now that we have a base to discuss i will work through your points:

1. Are they a new player?

This is irrelevant. You have the tools for easy learning and integrating of your skills while you level.
Sit down once in a while and read your tooltips and do some theory crafting yourself. If you can't figure out how some things work or should work, ask for help or read a guide.
Noone asks for perfection and optimization but for the basic knowledge of your job and how it works.
Especially jump potion users have to learn to play before entering their first duty hoping that all will end well.

2. Did they recently change their UI/Binds or both?

This is a case of personal responsibility and etiquette.
If you are not accustomed to your UI and especially keybinds to a degree that it impacts your performance so hard that you will get a hindrance to a clear or can't perform the basics you shouldn't do any party content.
Take your time to relearn your abilities or you just annoy or anger other players.

3. Are they having a bad day or are they feeling sick?

And another case of personal responsibility and etiquette.
If you're having a bad day take a step back and focus on yourself. Get comfortable with yourself, don't involve strangers.
Also if you are so sick that it impacts your performance to drop so hard that you will get a hindrance to a clear or can't perform the basics for that content you shouldn't do it. Get rest and cure yourself.

Could be any of these things or more preventing someone from performing well. and to be fair most of the time I find it is.

If you fall under your 3(4) points you shouldn't participate in any content that requires to perform "well" or at least "above average" or at the basic skill level of your job.
Your first point may be an excuse, but just maybe.
But all points are showing an absence of respect for your other party members and the content.