...Who loves to jump into melee range of trash mobs and Holy Nova spam. Don't be like me. I once ran into a group of trash after the tank gained aggro on them all thinking I would be safe. I figured I could keep shelling out Holy Nova and do some damage as well as heal right? Well 3 seconds later, I found myself face planted on the ground. Turns out those mobs like to whirlwind. I learned my lesson and kept my DPS to a distance.

...Who like to chain Levitate people especially when triggering Anub'arak. This is actually really annoying. And yes the debuff is removable by clicking it. Still, it does irritate people especially those who can't click it off if their UI doesn't display it. There's no real reason to levitate the entire raid. Doing it to run across the ocean is one thing. But don't do this crap during raids.

...Who don't remember to buff Fortitude after someone gets back up during mid combat. When players are dead, their buffs are wiped. When they get resurrected mid combat, they're going to be weak. It causes me to lose precious time when I try to look for them on my frames. I just slam Prayer of Fortitude and rebuff everyone in the raid to guarantee they've been hit.

...Who forgets they have anti-disease spells. So we've got two dispels. One removes magic and another removes disease. Keep it bound on your bars. I like to have Dispel as my E key, Mass Dispel as my Ctrl E key, and Abolish Disease as my Shift E key.

...Who continues to heal after a wipe has been called. You're slowing the raid down! Your leader just called for everyone to die! Stop healing and wasting time! Run to the nearest fire and die!

...Who doesn't realize they have mana potions and flasks for tough encounters. Unprepared raiders who are tackling bosses without the necessary consumables? What's up with that? Get some flasks when you're working on progression stuff. You might not need mana potions now, but it's better to have it just in case you do.

...Who never heals hunter pets. Want to really stand out from the rest? Have some pet frames shown. Watch as hunters lovingly gaze at you as Spot The Wolf manages to live.

...Who doesn't DPS during burn phases. If it's a straight up max DPS phase, don't simply stand there twiddling your thumbs waiting for someone to take damage. Be proactive and start healing. Chances are, your raid is alive. Take the time to pile on some DPS.

...Who DPS's when they shouldn't. Know when is not a good time to DPS. Stop tossing Holy Fires when the raid is taking massive AoE damage.

...Who fails to use Fear Ward when it is known there are mobs that fear. This is me. I sometimes forget to use Fear Ward. I'm a Dwarf too! I've had access to this spell since forever! Don't be like me! Make notes on which bosses fear and use it then. Faction Champions is a great time to use it.

Who blows Hymn of Hope when everyone's mana is topped (or is too far away). Your raid frames are up aren't they? My frames are set to display the mana bars of everyone in the raid. Browse through it and check once in a while to determine if it really is needed. If the mana's still full, there's no sense in using it.

...Who is way off on Pain Suppression or Guardian Spirit cooldowns. I admit, coordinating cooldowns with big attacks can be tough to do. You're too worried about healing the raid and sometimes you might be off from dropping a defensive cooldown on the player who needs it the most. This used to be me.

...Who never dispels on a fight like Hodir. When I play on my alts, it continuously pains me to see players stuck in Frost Nova or in a constant state of fear when such effects can be easily removed. Priests have an AoE dispel at their disposal. It's not difficult to point and use it. Sometimes a simple Dispel Magic can be more important than a heal.

...Who Power Infuses melee. I saw a priest cast Power Infusion on a ret paladin once. Please don't do it. There's other casters who will benefit more from it.

...Who Pain Suppresses a tank with an extremely minor threat lead. This is frustrating. I understand that some tanks take a huge beating and you can't bite back the urge to drop a cooldown on them. It's even worse when they have such a colossal time generating threat. Keep an eye on your threat meter for this one. If there's a DPS that's just under the tank, a simple Pain Suppression could tip that DPS player over and cause a bunch of problems.

...Who drops the Psychic Scream fear bomb on trash when there is no need to do so. There is absolutely no need to fear on trash. Raid groups should have plenty of crowd control already without a priestly need to fear. By screaming, who knows where the feared mobs will run to, right? They could pick up even more trash mobs. Or worse, they could yank the boss over. Do yourself a favor and don't voluntarily fear unless your raid leader green lights you to do so.

...Who comes into the raid completely devoid of candles in their bags to buff. I make an effort to keep a stack of 60 candles on my priest at all times. There are times when I've run out mid raid and it's embarrassing. It also sucks when you have to cast 50 individual buffs (between Fortitude and Spirit).

...Who just stands there. Do something! Heal! Dispel! Look productive! Don't stand there and look AFK! Run around and keep players alive!

...Who forgets to Fade when new mobs crop up. Whoops! I pulled threat once on an incoming mob. Fade is your friend. In fact, keep hitting fade every chance it becomes available. Watch as your survivability increases.

...Who forgets to activate Inner Fire. It's an extra spell power buff. Have it keybound to something handy and convenient. For me, I like to use Shift C. Don't ask why. It just happens to work out.