With the random dungeon finder, I've been getting in a lot of groups where people don't know what to do, don't understand, have never been in a heroic before...and hey, that would be fine.
See, I have no problem with people being new to an instance. That's totally cool; everyone starts sometime, somewhere. The problem is people don't try to learn.
What am I talking about?
Well, let's take three anecdotal examples from my experiences, shall we?
First, Oculus. Yay, Oculus! Some of you may know that I love Oculus. However, Blizzard has nerfed Oculus into the ground so hard I literally had a group member stand on the electrified floor without moving out of the sustained breath-beam-thing of a sky captain with little to no heals without dying. This is really teaching people get out of the fire skills, tell you what.
But I digress.
See, the whole group but me (on Sugarcake; almost all of my bad groups are on my huntard) and the Paladin healer had never been to Oculus before. So, the Paladin and I attempted to explain the layout, the bosses, how to avoid pulling a zillion blue drakes, how to use the drakes...and we got through everything by brute-forcing it, until we got to the last boss. Continual explanations, drake shifts to give them something easier weren't helpful. The tank couldn't even find the drake vendor, still, after wiping multiple times. No one was paying attention, at all. It's not even "vehicles are hard" at that point; it's "you're not trying to learn."
And then...Old Kingdom. Oh my goodness, Old Kingdom. I got this instance twice in a row, and both times I had to leave early because it was just not worth the repair bills anymore. I felt bad about it, but I just couldn't stay.
The first time, the tank had no idea where he was going. This is okay; everyone has their moments when they're learning an instance. But he wouldn't listen when the group tried to show him the correct way to go, instead running in circles around the first boss's area, pulling extra packs of mobs that actually ended up wiping us a couple times (because, hey, no one is controlling the insta-kill spell flingers, and when I try to freeze them in place the mage is purposely breaking my CC). It didn't help the healer was continually AFK (or unglyphed HT healing), either.
The second time in OK, the tank was "undergeared" (i.e. in blues). Now, obviously these heroics can be accomplished by "undergeared" people; we did it in the beginning of Wrath. However, this tank played like he was in ToC epics, pulling without worrying about control or even threat, really. So, of course, spell flingers were eating people, lots of wipes were had. After the second boss, the DK DPS pulled a second pack of adds for no reason and killed everyone but the rogue and I.
As the Rogue and I talked, we discussed how if we didn't Misdirect or Tricks the tank, the adds wouldn't get picked up; but if we did, then he would die. My CC would get broken. No one was using defensive cooldowns. The Holy Paladin was apparently half-awake, and the tank liked to die in a blaze of glory. Half the time the rogue was evasion tanking or I was kiting or my pet was tanking.
When the tank pulled an extra pack of mobs on his way back in, I apologized to the Rogue and left the group.
It is becoming somewhat common that I find people think just because it's easy, they can do it without any sort of thought or care. They try to brute-force everything because many things can be brute-forced. They don't take into account that their gear can't handle it, that some things still will one-shot them, that they need to pay attention.
I could see how the current content would breed that mindset. After all, I remember logging in early when ToC first came out, getting extra consumables and reagents and feasts and preparing myself to stay on late, because this new boss had to be hard. After all, it was after Ulduar, and with only releasing one boss at a time, it was going to require some work, right?
We killed Beasts in 2-3 shots and went back to Ulduar. This left us totally unprepared for Hardmode, as we'd been lulled into a false sense of security by the ease of normal.
Some of it could also be that people skipped the "hard heroics" like OK and Oculus with gear resets, and now think they can just merrily romp through collecting their badges with no idea what they're doing. Which is, in essence, the same thing.
Just because something is easy doesn't mean it can't kill you.
Just because something is easy doesn't mean you don't have to pay attention.
Just because something is easy doesn't mean you can slide through it.
Just because something is easy doesn't make you immortal.
So pay attention. If you don't know, ask. Do your own investigating, even if that means simply reading the text supplied to explain how your dragon works. Slow down. Mark groups. Don't break CC. Look where you're running. Listen to your group members. And remember:
Just because something is easy doesn't mean you can't mess it up.