Enervation and the repetition factor
One of the reasons I found Zul'Gurub and Zul'Aman so uninspiring after running them to gear up my main before raiding was that they were the dead end of non-raiding content. The gear was a half-step below Blackwing Descent, Bastion of Twilight and Throne of the Four Winds, the three raids available at the time, setting up the dungeons clearly as places to go to fill slots where you just hadn't gotten lucky on a drop. They were also used to grind up valor points to buy set pieces and other epics from the vendors, which did give you a chance at pieces as good as raid gear.
Once you'd run them enough, clearly you'd no longer need valor points or gear from those dungeons. Worse, because the ZA/ZG gear wasn't really as good as then-valor and now-justice point gear, you quickly only farmed those instances for valor points and sharded everything that dropped. Simply put, sharding gear isn't fun. It may be inevitable, but when even undergeared alts pass on stuff because they know they'll be buying better in a day or two, it's a problem.
With each dungeon being fairly long (up to seven bosses in ZG, if you hit the two optional ones, and six in ZA), running them for your weekly valor fix became repetitive. Worse, doing it on multiple alts became mind-numbing. Once I'd run a third alt through them to the point where he could no longer benefit from gear from the dungeons themselves or from JP/VP gear, there was no interest in gearing up another alt. Even with the shaman, who wanted different gear from them and needed gear for bother enhancement and resto, it got to the point where I could predict exactly what was going to happen in each group the second I zoned in.
With raids offering not only better gear and more of it but also more interesting and varied fights that I didn't see over and over again, I ended up spending the limited time (10 or less hours a week) I spend on alts PVPing or working on professions. It's not that ZG or ZA are bad dungeons. They're not, not at all. As we discussed before, it's more that they were basically the only progression left to my alts, and two dungeons simply weren't enough. Yes, you may argue, I could have run the lower dungeon tier of starter Cataclysm heroics if I was bored of ZG/ZA, and I did, but when I did, I knew I was cheating my non-raiding alts of VPs for gear.
In essence, it comes down to whether or not you can justify to yourself not only doing something you've done before, but doing it in the exact same way. There isn't really anything you can currentloy do on a non-raiding alt for valor points that's worth doing except run ZA/ZG.
Options delay stagnation
With the coming of Raid Finder and the new system for heroics (all currently existing heroics will be folded into one tier, while the Hour of Twilight dungeons will be a second tier, and both tiers will reward the exact same valor points), I'm rethinking how to gear and alt and generate VPs. The new VP cap of 1,000 a week isn't the issue; it's very slightly less restrictive than the current cap of 980 and still too low, in my opinion. (The 1,260-VP cap from launch was near perfect.) But the flexibility of the system -- which will allow you to reach that cap via either tier of heroic dungeon, or purely from raiding, or half from Raid Finder and half from heroics or raiding with your normal raid -- is brilliant in terms of its long-term use.
Once I get bored of slamming my alts face-first through the new dungeons, I can shift into the larger pool of heroics and see different dungeons again. Let's be honest: With ilevel 378 and better gear (Hour of Twilight gear is 378), we'll be steamrolling the older content, but it will be a nice change of pace. It also means that if I'm not geared enough to run HoT, I can collect my 1,000 a week in the older heroics and buy 397 epics from the valor point vendor to bootstrap me into Hour of Twilight. I'm not punished for running older heroics.
All of this is before even taking Raid Finder into account. Not only will there be valor for those runs, but I'll be able to see the fights in a simplified form before I raid them on my main, and I will be able to gear up my alts via drops that will be at least 378, I would assume. (It's stated that the 10-man and 25-man normal raids will drop 397 gear and that Raid Finder gear will be a lower level.) What this all means to me is for the first time since Cataclysm launched, there will be superlative flexibility in how you gear, especially for an alt. I'm not forced to craft or PVP to get weapons that I'd be willing to take into a raid, for one example. For a while, the only DPS shoulders available to a non-raiding plate DPSer were the ones in ZA. Once you had those, you could forget getting better unless you were willing to have a ton of resilience wasted on your gear. Now, you'll be able to get shoulders from Hour of Twilight or from Raid Finder, which is two more options than anyone has now.
I find myself really looking forward to being able to pick different ways to pursue my characters' paths. I'll still raid on my main, but now it won't feel so terrible trying to gear up an alt and finding myself faced with a choice between the best possible option or a bad one. While not actually a Hobson's choice, it felt like one. Patch 4.3 will give a wider variety of players a wider array of choices, and I'm pretty excited about that.
Brace yourselves for what could be some of most exciting updates to the game recently with patch 4.3. Review the official patch notes, and then dig into what's ahead: new item storage options, cross-realm raiding, cosmetic armor skinning and your chance to battle the mighty Deathwing -- from astride his back!