One thing that amuses me is you see learning parties, where you get the impatient guys that will rage quit after 10-15 minutes or 2-3 wipes.
you see clear parties, where people have come close to beating the fight. kind of the next step from a learning party logically
then however you see farm parties, where people have finally cleared it once and now declare themselves uber professional and have the fight "mastered"

never see a party that sits somewhere between clear and farm.. people clear it once and suddenly assume there's gods at the content.

personally most issues I encounter in farm parties come from lack of communication. everyone just assumes everyone is doing the exact same strategy and that's often just not the case. common example seems to be the mt expecting ot tank swap a mechanic while the ot thinks mt will just cooldown through it. bam! dead people. or the reverse where the mt isn't expecting a swap and the ot moves in for one and bam both tanks eat a massive debuff.

or going back to arr t9 farms were horrendous in my experience. some folks would stack centre expecting golems to be dropped on edges leaving that nice little "safe" area in the centre. other folks would stand on edges expecting golems to be dropped in circles, then you see a golem in the circle and one at the edge too close together merge wipe, everyone rages cos the other guy was doing it wrong..

same in bis ex where healers don't get the dragon killers / generator cos they think a ranged dps /tank will. dps won't get them cos they think the healers will before you know it islands at 50% and you haven't even started smashing the carapace.... wipe then rage....

it's almost as if people believe there is only one way to clear a fight and that everyone has done the exact same strategy as them. I wonder how many wipes would be prevented if people took a minute to make sure everyone had the same strategy / plan of attack