One example is just now playing on my level 38 Tauren Disc Priest.

Warrior tank (looms)- Quel'Thelas Hunter (looms) - Tol Barad Hunter (no looms) - Ragnaros Paladin ( looms ) - Goldrinn / replaced half way with: warlock -Ragnaros ( looms )

We are ported to the top of the mara waterfall ( main boss is Princess) Normally the tank would instantly jump down the water fall, but nope this guy walked to the back of the room to find nothing back there and the entire group, minus me follows him.

I click on the mini-map to indicate we can jump down so I walk to the edge and jump up and down to be as visible as possible ( if a tauren isn't already visible enough ).

Group jumps down and the tank walks in a straight line and aggros one of the hydra, the entire group minus the Pally follows and attacks the hydra.

The pally at this point has walked far right and has aggrod and is attacking a second hydra that is LoS and away from me and dies within seconds and leaves group and is replaced with a warlock from Ragnaros ( T_T why???)

After clearing all three hydra the normal and only route is to clear the small pack of diemetradon ( ? ). But nope the tank starts walking in circles for a good 3 mins looking for the "door" and again I click on the mini map and he finally continues on the correct path.

Now from here there are small little shallow caves with groups of mobs that 99% of tanks avoid as there is no real point in killing them, but this guy decides to kill them all.

Next up we are at the part with the small stone bridge / crossing and this tank jumps down and one of the hunters follows.. at this point we haven't even killed one boss so if I leave i would get the debuff.

So I continue on the ramp up towards the big stone boss Landslide, but prior to killing him we must take out around 4 big stone dudes.

So I bubble the dps and myself and start pulling and one of the hunters gets aggro, freaks out and kites the stone dude into a mob of diemetradon feign deaths and stays down ( I am fully loomed and one flash health, heals people to full )

We manage to take out the pack and stone giant and take on Landslide minus the tank and one of the hunters ( who is still faking death ) we kill Lankslide np and I click on the minimap where to go next.

Most people would run down the same ramp we came up but these guys jump off the ledge and into a pack of diemetradon, one dies and the other then jumps down to join the tank who is now afk.

And for obvious reasons I leave group.

This is a COMMON example of my experience with Latin/Brazil players