A versus The.
Are you merely 'a hero' or are you 'the hero'? That's where 99% of the problems with ESO come from and until Zenimax decides which one it wants to serve the problems will never go away. Ever.
The entire game from level 1 thru VR14 can be played as 'the hero'. Much like all previous Elder Scroll games you and you alone save the world from destruction. You rescue the fair maidens -- OK, I preferred rescuing Stibbons

You thwart the evil henchmen. It's a story and you're the star -- the only star.
Well, almost.
Unless you over-level taking down dolmens will knock the heroic wind from your sails pretty quick. And even with a veteran toon soloing some of the public non-veteran dungeons is a harsh let down. So you start grouping but you find that all the other people you group with are, for the most part, interchangeable self-sufficient heroes just like you.
I've played seven toons into veteran ranks. Heck, I've finished Cadwell's Gold three times. I've seen just about every place there is to see in Tamriel. And I've done it lots of different ways. I've played Tankblades and Stick Knights, a stamina build Templar, and a mage in heavy armor. In the end they all have to find ways to effectively DPS mobs, dish out some CC, and heal themselves. Eventually they become, apart from their racial features and tinted armor, copies of each other.
And I feel that's a big part of why grouping is looked at so poorly in ESO. There is nobody essential for all but a precious few of the group encounters. With enough DPS or enough healing or enough armor you can power your way thru any encounter. How many times have you set out on a mission with 3 dps and a tank because you couldn't get a healer and in the end found out you really didn't need one because the tank and the nightblade both had Restro staves maxed out and you killed things so quickly it really didn't matter most of the time anyways?
So Zenimax has a problem. They want to encourage more group play. However, the only way they seem to have to get people to play together is to put mobs of powerful monsters with immunity to various effects in an enclosed area to force you to get some help. What if instead of brute force being the only lever they had they tried something different? Maybe the only way to take out a boss was for a shadow cloaked thief to sneak up behind it and garrote it? If a mage could cast a barrier that let your group actually get safely away? Maybe it would require a Templar to appeal to Akatosh for divine intervention? What if instead of every boss just being more hit points and damage there were some that were truly special?
What if the reason people grouped together because they could make a meaningful difference in the battles ahead and not just be 'a hero' but 'the hero' even in a world full of heroes? Imagine this encounter...
Group lead -- Thief of Haarts, we need you to go stealthy and scout the room ahead. Check for traps and see if there's anything big inside. (Why are the bosses always in the same place?)
Thief of Haarts goes into the shadow realm, by leaving the physical realm she can't attack or be attacked for a full minute, a new stealth ability in Update 6.
About a minute later she returns and gives her report. There are two traps right past the door. I can disarm them but I'll need some cover. There's a stone giant looking right at the door way and he looks mean. Eleboris, can you cast your Stunning Radiance to blind the monsters while I disarm those traps?
Eleboris -- Sure thing. Not a problem, it's fully recharged after I last used it 15 minutes ago. Remember they nerfed it down to only 10 seconds with the last patch to 1.7 so no goofing while you disarm those traps.
Group lead -- Kangor, get ready to shield bash the stone giant as soon as he's blinded, we need to hit him for all we can when he's vulnerable. I'll start laying down the healing as soon as you engage. Let's do this!
Thief of Haarts sneaks up to the entry and waits for Eleboris to cast his spell. The giant howls with rage as the magic washes over him. She begins disarming the first trap.
Group lead - Hell! He's not blinded! He's coming straight for her!
Kangor charges in and knocks the giant off balance but because of the traps the healer and the mage can't get close. Oh well, ranged attacks are their forte anyways. And the engagement is in full swing. The giant becomes enraged as the battle proceeds and gets noticeably larger -- much, much larger.
Group lead -- it's no good! We can't take him down. I'm going to call for divine aid! I'm using my weekly Akatosh Intervention! I hope it works!
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