why do you heal?

[Lobotomite]

Long-winded answer to a simple question.

1) I play a "healer IRL" like OP.
2) I sort of fell into it. When I first started with MMOs, I was originally planning on being a ranged DPS, but I was asked to heal a group in a dungeon. I got compliments from the rest of the group, so I figured I would stick with it, especially after learning that healers are generally in much higher demand than DPS.
3) I heal because (traditionally) healer roles in MMOs require a set of skills that I'm good at.

DPS involves a lot of serial processing--being able to memorize a script [ABCDEFABZCACSJA] (repeat) and executing it in real time. "Good" DPS know how to execute and tweak the script so that downtime from avoiding mechanics is minimized.

Tanks also have a certain amount of execution from a script (which rotations will allow me to get the most threat), but they need to have wide battlefield awareness and be "big picture" thinkers so that they can respond to stray mobs that peel off. A certain amount of spatial thinking is also required, because they're responsible for positioning the boss or adds in a manner that will minimize the amount of downtime for DPS and unnecessary work for healers.

Healer is very different from the other two roles and is much more intuitive. It's generally a role that you either love or hate. I think that most healers think of their moves situationally instead of serially (the boss just used Heavenly Heel and the tank is currently at 40% health, therefore an Essential Dignity or Benefic II would be most appropriate at this time).

Healer also requires a couple unique skills: the ability to prioritize or triage (everyone is at 40% health. Should I patch up everyone at the same time, or focus on the tank?) and the ability to clutch (making snap reactions to unexpected damage before the player at critical health dies). Outside of clutch situations, healer is more catered to slower, deliberative thinking--if you're performing your role well, you don't need to be constantly busy and slapping out a move every GCD (at least in games that don't demand as much DPS from healers as this game does.)

[Seoulstar]

Because I generally like to help people.

[Eul]

Fast duty, mostly some of raid/trial phase healer just focus healing, and also I love heal + DPS.

[Kacho_Nacho]

Lots of reasons!

Healing truly matches my personality. I like taking care of people and offering succor! I even worked in the medical field in real life behind the scenes before my health took a bad turn.

Watching those health bars and keeping characters alive is so satisfying. Triage keeps me actively engaged in the game. I watch the party's health and choose the best spell for the situation. No stressful spell rotations to memorize.

As a healer in other games, I tended to be included in raids. Also, my waiting queues were shorter. I have found the same in this game. It's nice to be needed.

And lastly, I love the spells themselves. It's nice to be able to quest and know that I can easily replenish my health as needed. It's a big turnoff to me to keep dying while leveling.

[Warr_of_Lint]

I tried healing at first because I always loved white mage robes. The red triangles in stark contrast to the pure white robes is a simple yet vivid icon in the Final Fantasy series. I have since branched out.

Regardless, I've enjoyed healing from the first day. Everyone looks outward at external threats, but healers also look inwards and tend to the party. I feel closer to my party members when I heal, which is natural given more of my spells are spent on my friends than my enemies. Then there is the feeling of euphoria when I manage to save a party member from near annihilation with a timely spell.

[Alisane]

Like several others have mentioned, I too am a "healer IRL" so I suppose it was a natural choice.

I really enjoy the diversity of the role. Some encounters have a lot of single target damage, some lots of AOE, some a mix of both. It's fun to know what is needed when and react accordingly. Some encounters don't have much damage at all and then you can stance dance and add to DPS. But really I enjoy supporting my party members and keeping them going! Nothing is quite so satisfying as seeing the healh bars go up after a big heal, or giving an enhanced balance and time dilating it on that great BLM. My secondary class is paladin which caters to group support, so I think that says a lot about my attitude toward that anyway.

I have never really enjoyed DPS. Pushing the line with damage, rotations, and mechanics always seems so overwhelming. Which is funny because I know a lot of people feel that way about healing!

[Kerrigen]

Because this is the closest role to 'support' we have in this game. I like that my contribution to the party's success is non linear, tactical and situational.

[File2ish]

I heal because I was generally put in the healer role by my friends (an early-ish example being FF Crystal Chronicles on the Gamecube. Once we found the cure spell in the dungeon I was healer). It's the role I knew and genuinely tried to avoid when I could. But always found myself choosing jobs and classes that had healing abilities (but not focused).

In FFXI I loathed healing because of one bad experience. Got really pissed off when, as a budding Red Mage in my first Yuhtunga Mandragora leveling party, I was forced into a healer role while we had a White Mage in the group on top of a level 75 RDM healing us ("PLing" if you will). "RDM HEAL, Dia HASTE, REFRESH ONLY!" they said (and I lacked the latter two). That's when I picked up dancer (I started around the time WotG came out). Loved it because it had a ton of utility, could attack without being yelled at and I never had to be main heals.

And now I main heals in XIV. Go figure. I actually started the game as Archer/Bard and didn't pick up a healer role until I made my alt character and leveled CNJ/WHM a bit. I liked it, got it to 50 on her, then got it to 50 again on my main guy and made it his main role. I've accepted that I like the role. It's fun and can be challenging.

Now I'm just waiting for Red Mage in XIV, regardless of what role it is. It is, after all, my favorite job :P

[Reinha]

1) Healing is both reactive and proactive in nature. Nothing beats pre-casting and landing a fat aoe heal right after group wide damage, or quickly casting an instant heal to save a failing tank.

2) I get to actively focus on my group as well as enemies. This helps me understand encounters faster and from multiple perspectives.

3) The dps "rotation" is enjoyable.

4) It fits the image I've developed of my character. Also better glamour options.

5) High skill ceiling. Fitting your healing output to the damage taken, avoiding overhealing, adjusting to burst phases, stance dancing, positioning to minimize movement, mp management... There's always something to improve.

Lot's of people have mentioned the control they have over people's lives, but that's not on my list.

[Atoli]

I thought about the question again and found another answer:
I heal because someone's HP are dropping and no one else is stopping it :P

Yeah. I like that answer better x3
Because it also includes me spamming heals on other classes than designated healers when it's necessary xD