I mean, let's think about this. Tanking might not be Brick Tamland level stupid, but it isn't a far cry from it, either. We've decided to take it upon ourselves to stand between our team mates (whether they're a Guild group or a PUG) and their otherwise certain repair bill. We rush up in front of big, scary monsters -- and taunt them. When you engage in that kind of behavior, there's some pain and death for you on the horizon, and it's chugging toward you pretty quickly.
I don't want to minimize the other key roles in an instance. Without a healer, no matter how good a tank you may be, you're not going to be standing there for very long. Without DPS classes, barring some truly amazing damage output from a tank, that bad guy just might never die. And, obviously, Crowd Control can be pretty darn key. (Even if I, as a Pally, sometimes drive our crowd controllers a little bonkers. Sorry about that, guys.)
We had an interesting Breakfast Topic some months ago about this subject. The answers given were as wide and varied as you might expect from a vast audience. But there were some common themes. I definitely think there are a few, core reasons most of us can agree on.
1. We will rule the universe as healer and tank.
When I started my Paladin, I admittedly did it for roleplay reasons. I'd just finished the Tirion Fordring quests on my Hunter, and I thought he was two shades cooler than the Fonz. Sure, I've always had a little love in my heart for the Knight in Shining Armor thing. But I leveled as a Protection Paladin up to the 40s, and then let my tank rot in an inn for many months. It was only later, when a good friend of mind started a Holy Paladin, we hit upon some killer synergy. A tank and a healer, running together, could always find instances.
It helps that my girlfriend plays a Hunter, also. That means, at any given time, we have a tank, healer, and crowd control, ready to go. Any Heroic we wished, any time the three of us logged on. It's pretty easy to find two DPS, at any hour of the day or night. While it may take a few minutes to find the right mix of DPS for the instance we're after, we're not often left floundering about, unable to fill the group.
This isn't a unique experience -- quite a few of us became tanks for greater control over our gameplay. While anyone can choose "not to do instances," most tanks (and healers) feel like they have more self-determination about which instance they do go to. That level of control is a strong reason to play a tank.
2. I am key. I am vital. People look for me.
The Tank Shortage probably helps with this. And I've mentioned above the sheer power of running a healer/tank pair and finding groups for instances. But even by my complete lonesome - I rarely (if ever) lack for groups. And what's more, my contribution as a tank is visible and obvious.
That does mean my shortcomings are equally visible and obvious. If I fail to hold aggro, no one's going to miss it when Magtheridon swings around and stomps my little caster buddy. And while I can make excuses ("POM+Pyro was your very first attack?!"), if I'm not performing, folks are going to notice.
The tank is one of two must-have classes for every instance. (The other is a healer.) As a friend once said, "Every class can DPS." Every class has a DPS spec, though I guess we could argue which ones are most effective. But there are three (soon to be four) tanking classes. You choose to tank, you go out of your way to do so. You sacrifice for it.
A tank lacks the elegant Character and Pet combo of a Warlock or Hunter. It lacks the sneak-and-kill of a Rogue. It lacks the crowd control and utility of a Mage. These are beautiful classes, don't get me wrong. But if you're a tank... you're a tank. There's not much pretending you're doing anything else. We're rewarded for it by that prestige of vitality.
3. I get to set the pace and strategy.
I get to set the pace of the instance, as long as I'm careful not to out-run my healers. I should be responsible, and not go bonkers, pulling huge hordes of NPCs while the group's mages, 'locks, and sundry are desperately trying to get a sip of water. But that being said, the pulls tend to wait for me, and I tend to decide when to fire the gun.
I can make the instance go faster, according to my ability. Especially as a Paladin tank, if I can handle more mobs, the quicker the instance is going to go. I'll hold 'em -- y'all just pew-pew until your gun goes dry.
I also tend to decide "How are we doing this?" Are you sheeping that orc, or am I going to smash him in the face with a hammer? People tend to look to their tank for that kind of decision. I think it's a reflex -- after all, the tank's the one rushing up to the front line, and volunteering to pay the first repairs.
That tendency puts us in the position of strategist. A tank gets to figure out the nuances of the pull. A good tank should listen to the committee (your group), but it often falls on him to make the final decision. And that's pretty cool.
4. I'm good at it, and it is fun.
I really hope everyone has at least a little bit of this answer swimming around in their hearts. Tanking is a pretty tough job -- if you're not good at it, it's going to get rough incredibly quick. There are many, many pulls in which you can hold aggro just long enough to die yourself, and then your off-tank or DPS can handle the rest of the fight. If that happens, you're looking at a pretty good sign of a not-great tank, and a not-great tank racks up bills pretty quickly.
If you're not having fun -- well. I'll actually cut this one a little slack, in my mind. Sometimes, I don't have fun tanking. It can be because the group isn't coming together quite right, or it could be that I'm just not in the mood. But I'll tank something anyway, often because it's a way to help out my friends. I like to see my friends happy, and if they're in a good mood, then that's going to provide a little bit of fun for me, too.
I like being able to help in a meaningful way. Most of us do -- heck, MMOs are social games, and helping each other is a part of being social. So, being a tank puts us in a great position to capitalize on our class, and our help our friends.
5. Dude, it's hardcore.
Yeah, serious. Gruul just tried to hit me...and I dodged. Or, perhaps, I just got crit for 10K, and with the help of my friendly neighborhood healer...brushed it off, and got back in the fight. That's not something other classes can lay claim to.
Hell, our fundamental role is to get hit. It's a little bit between a macho man ploy and a bit of masochism. But no one can deny - if you can take a beating from Illidan, you're made of some tough stuff. That's something special.
So, these are my reasons for being a tank, and I think they're reasons most tanks can agree on. These help define our role, and give us some kind of understanding about why on earth we do this. A happy tank is a better-performing tank.
Good luck out there, and get hit a few times for me.