RNG is not an excuse
I'm going to rant here a bit because every time I see someone mention bad luck (or RNG) it makes me angry. I'm pretty sure most raiders hear "bad luck, couldn't have done anything about it" multiple times in a single raid and I just want tell you that almost every single player who blames bad luck for wiping is a fucking idiot.I hate when people blame luck and that's the end of it. Somehow the general attitude seems to be that shit happens and there is nothing you can do about it when the players' attitudes should be "FUCK! That's not supposed to happen! How can we survive this? Could this have been prevented?".
For example pre nerf 25 heroic Al'Akir phase 1 which by far was the most skill intensive thing in this tier. You had to work with timers that aren't 100% certain: AA might be casting Electrocute on tank when AA was supposed to do Wind Burst which messed up everyones plans. You had to work with randomness: tank had to turn the boss which then made tornadoes spawn in a certain way that in 30 seconds they would collide at the same spot, which at the same time had a lightning strike spawn while wind burst is being cast. And add on top of that the general difficulties even without those special situations. Half of the platform was unusable, the players had to think themselves about their positions and the position of others so they don't get everyone killed.
All in all, it was a fucking nightmare. We wiped there for days without significant progress. We would pull and 3 guys died within the first 30 seconds. Rarely we would make it to p2 with only a couple of deaths. We did this again and again for days. Other guilds weren't even trying this "RNG shit boss" (a quote from a world top 10 raid leader).
And then suddenly on the fourth day everything clicked. Now we were getting to p2 with 80% of our pulls and still had everything under control (not too many deaths etc). Players were surviving things easily that were killing them a day before. These were the things that most people would claim "bad luck" ("bad" timings with tornadoes, lighting strike and wind burst). Do you think it was because of bad luck we wiped there for days and then suddenly we have a day with incredible luck where everything goes as planned? Hell no. We learned to play properly and we learned to avoid getting in to situations that are unsurvivable.
My favourite example in ICC was getting green fixate + Malleable Goos on top of you on Putricide and then claiming that was bad luck and nothing could have been done. The guy died because the raid played badly. I'm 100% sure there was someone who didn't use their guardian spirit, pain suppression, sacrifice or whatever. If they were all used, guess what? That's why you have combat resses. A raid can survive those kinds of things if they play well enough. But after spending your combat resses on players who died on stupid shit and then the above mentioned situation happens and you wipe because of it, it's once again bad luck in most people's minds. They just don't seem to get that bad playing was the reason they didn't have that combat ress. They are just too fixated to that one particular thing that just happened.
Just to emphasize: bad luck does exist. But you don't wipe because of bad luck, you wipe because you couldn't handle it. I realize I'm not the average raider and I raid with a pretty incredible group of players. But the point I'm trying to make is that don't blame bad luck and just end it at that. Try to learn how to avoid getting in to situtions you just were in.
We encourage our players to point out how they saved the day after something unexpected happened and the raid survived. It's not uncommon to hear "Saw that sick move I just did? Saw how I saved the raid there when you fucked up (or as most people would say "had bad luck") because I'm just better than you?!?" in our Teamspeak. Adapting well to changing situations is what makes a good player great and guilds/raid leaders should encourage that.
Of course sometimes there are things you just couldn't avoid even if everyone was playing perfectly. Those situations are very rare and you can just shrug them off but you are very wrong if those kinds of situations happen more than couple of times a week.