There's been a lot of whining about badge loot from the raiding community lately, especially in light of the badge rewards coming in Patch 2.4. I don't really want to get dragged into a discussion of the larger issue of badge rewards, but I'd like to focus on one element that is has not really been discussed so far. In my opinion, a large part of the impulse behind the complaints comes from Karazhan fatigue.
Karazhan was the first raiding instance of TBC. It's the one we've been doing the longest. It's a good instance, but still, veni, vidi, vici. It's way past time to let Karazhan go. Yet it is the single best source of Badges of Justice in the game. One evening nets you about 22 Badges. And so we run Kara on our mains for Badges, we run Kara on our alts for Badges, and so a lot of us are pretty sick of running Karazhan.
Zul'Aman had potential as a replacement for Karazhan, but ZA is on a three-day timer. This means that the rewards from ZA are balanced around being about to do the instance twice in one week. ZA nets you 13 Badges for one evening of work. This means that you should always hit Karazhan for Badges first, and ZA is your second choice.
I've stated my opposition to short timers before, but that was mostly on scheduling concerns. But the distribution of loot is also a concern.
A newer, harder instance should be more attractive to players than the older instance. If you can clear ZA, you should choose to clear ZA over Karazhan. No 25-man chooses to farm Serpentshrine Cavern over the Black Temple.
Imagine if ZA was on a 7-day timer, and the loot was balanced appropriately. Now one evening would net you 26 badges. You'd get 2 higher quality epics per boss. And there would be a chance at a couple of Bear Mounts. If you could do ZA, you would choose to do it over Karazhan. It's harder, but it's also strictly better in terms of rewards.
The higher end raiders would most likely drop Karazhan completely, and move on to fresher content. Smaller guilds would have greater incentive to master ZA. In my opinion, putting a 3-day timer on ZA was a mistake. It has caused us to linger for too long in Karazhan, and the resulting Karazhan fatigue is an toxic element in the state of endgame.