For the shinies and also it's more fun that normal modes.

I voted loot, because that used to be my drive: getting gold keys and a chance for a helm.

But the recent introduction of the Cyrodill vendor has drastically reduced the amount of time I spend in dungeons.
Gold keys have no value to me anymore, and I don't have the will to farm a specific dungeon for a helm anymore either.
I bought all the Helmets I need.

The only dungeons I still run on a semi-regular basis are vWGT and vICP.
And those runs are loot driven (non Monster sets), although I like the challenge.

Hard to answer your poll as you ask for multiple different things.

vMSA I do purely for loot. In my opinion it's the least enjoyable content in this game, so I enter it thinking "I hate it, I hate it, I hate it" and then in the end when I get a robust winterborn ring I know I just wasted time and potions.

vMoL I do for the challenge

nMoL and SO I sometimes do for the challenge (with 5 or 6 man groups)

AA, Hel'Ra and DSA I currently only do for loot when it's weekly (miss the times when dsa was actually challenging and fun content :'( )

4 man dungeons I currently mostly do it to either level undaunted on a new char or because I'm on ts with nice people and want to play together with them. But I'd love it if they would pose some kind of challenge again.

I'll do it if I'm interested, (which is very rarely), or I'll do it if my Guildmates suggest a run.

Otherwise it's nothing but Questing for me.

I only quest and RP. Not interested in the endgame stuff at all.

Nice to see varied answers, seems it's not only me that merely endures it. Guess I'd probably be happier just dropping vet difficulty, there's only so many times you can get one shot by random mechanics and still accept it (cough round 7).

Did the silver daily today, never done the vaults of madness before, was great fun. Even had a level 19 dps, that only did single target dps. But it's much easier to accept that on normal, as people may be new.

For fun

It depends on the content.

It's a combination of "for fun", "for the challenge", "for the loot", and "because my friends do it".

vMA: First clear was for the challenge and not wanting to feel left out being surrounded be people who have cleared it. The next few clears were to make sure that the first clear wasn't a fluke. After that, I do it only for the loot and would not keep running it otherwise.

vMoL: Attempting to do it mostly for the challenge and because I really like the people who I run with. I don't care about the loot since it doesn't really excite me.

vICP/vWGT: First clears were for the challenge. The next few hundred clears were for loot. I now have 3 sets of SPC (one of them in perfect divines) and I've given up on bending over for RNGesus for Scathing, so these days I run them only when friends ask me to.

Other 4-man content: Mostly for the loot (helm farming or pledge key farming). But now and then I will solo or 2-man them for fun/challenge.

I used to, almost every morning. But Maw of Lorkhaj started dropping white items on EVERY... SINGLE... CHEST and this, plus the fact I've got myself messed with something else in RL, made me stop.

I used to like to run for achievements. I still need speedrun in Sanctum Ophidia and the veteran stuff of Maw of Lorkhaj but in my timezone people just don't do them, so screw it

For fun. Challenge is a close second. I prefer something cooperative over solo content like VMA though.

For Achievements.

For fun and achievements.

I do trials with my guild for fun and accomplishment and 4-man dungeons for achievements and experience (daily random). I would do WGT for loot but I think it too grindy to get the pieces you want...

love the group content and have so many build ideas always needing new helms and shoulders and trials are just epic when i can