Because they've bastardized all the rogue abilities and handed them out to every other class. The rogue brings nothing (like a group buff) to the raid that another class can't bring. And, their only real job... dps... and they are not even best at that. It's alright though guys...... GHOSTCRAWLER IS ON THE CASE NOW!
hell yeah, i always thought to myself "jeez rogue feel so dull lately, if only i could bring a buff to the raid, wich i can click each time after a wipe, then the class would be awesome again!" ... uhm yeah /sarcasm for those who didnt get it 8>
wanna know the problem of rogues? maybe some of these will help : opening with your ambush, getting in a nice crit and only having it crit for 20k... -seriously, w t f?!
highest dpsclass, maybe so but only because we got sooo much passive damage going on that its mind boggling! 70% of the class is pretty much running itself while you yourself only push some of the mediocre hitting abilities in order to buff your passive damage even more! and not to forget, you have to buff your passive damage repeatedly every x seconds and you also need to stand in perfect proximity to the target for it to work!
oh, and did i mention that rogues stuns, slows and movementimpairing-stuff are all across the board totally laughable?! in vanilla, you could literally stunlock somebody to death(wich ofc was imba, but this was waaay before insignias, dr, resilience and blizzards "lets reduce burstdamage only for rogues!" -policy) and today you cant even bring em below 75%... <--- this is also a huge problem for our overall pvp-dps since most of our damage comes from autoattacking and since a long time now, players "nonstunned" and/or "nonmovementimpaired"-time of a pvpfight has been increasing drastically, wich also allows those people to simply walk 5m and nullify the rogues damage completely... (yeah yeah,"just move your ass then!" im ofc also considering all the slows, stuns, and movementstoppers from the other classes!)
also: wtf is going on with my hotbars lately? i have like a 100 skills to equip on them, in order to react to all the different situations... i mean wtf, do i look like an octopus to you?!
rogues were simple to play, rewarding when effort put into learning the class to the fullest and fun to just stand in blackrock and gank unsuspecting people by stunlock killing all the undergeared ones...
today you get dozens of different abilities, all with different uses in different situations, and if you cant use em all you instantly lose to almost any normal pvpencounter because your enemy can nullify your whole usefulness by bashing one single button - and no insignia in the world is gonna cover the distance you have to walk to your target while being 70% slowed...
yeah, i dont even know how i keep myself playing my rogue.. maybe its just nostalgia from back in vanilla.. or maybe i just like the feeling of being horrifically abused in almost any pvpfight.
There's several factors leading to rogue downfall. As a former main rogue player, I can see some of them, so in no particular order:
1. Rise of the hybrids. Let's be honest, in Classic and BC the pure dps classes actually did more damage then the hybrids. I still remember the idea that hybrids should get a penalty because they're hybrids stated by developers.
2. Removal of rogue specific things and giving them to other classes too. Ever since classic druid had stealh, but that wasn't that much of a problem. Then, all of the sudden, in Wrath we got another melee class that, unlike rogues, was not a glass cannon and yet still used poison like abilities, the death knight and its plagues. In Cataclysm it was even more change, hunters got a form of stealh too, now there's a ranged invisible character. In MoP we got the brewmaster, a ninja like character, something that the rogue was supposed to represent, now taken away from them too. Now, with 5.2, I see even what's left like detect traps, one of the last things that rogues had unique, is being nerfed... and for what reason?
3. Stalling in rogue design. Look at all other classes. From expansion to expansion you see tons of changes. Let's take an example. From Classic to BC paladins were actually made viable, from BC to Wrath paladins got a few new seal mechanics and such that they needed to use, from Wrath to Cataclysm they got that light power and stuff etc, I won't dwelve into a long discussion, but the idea is that the class was somewhat reinvented while still keeping the core there. Now look at rogue. A melee damage dealer whose damage comes mostly from white attacks and that uses poisons.... has there been much reinventing? A.... there was a try with subtelty in Cataclysm, and it worked a bit... and then it preety much got wiped with MoP. Look at patches around, at every few patches you saw how some classes got some new abilities, new effects, new something. Now look at rogue part. In many cases it's nonexistant or at best you get some number changes of abilities.
The idea is rogues are still almost 90% as they were in Classic, and that makes them... boring. Why? Well for old rogue players because not much changed, and for new players because rogue functions after the design of Classic, as in many quirks to make your life harder that are useless. Oh, that mob died just when you were 5 points on it? Bad luck, well, here's an ability you can use every 3 min to change that, but that's about it. Oh, you need to change targets in a fight? Bad luck. etc.
4. Rogue specs. This was kind of a last thing. Since MoP all rogue specs are more or less the same. Use X ability to generate points, use Y ability, don't forget Slice and Dice. The end. So the homogenization between specs makes them feel all the same only with different names of abilities. Until recently in MoP combat was the spec you used for more mobs. Well with the proposed nerf to that ability, now they're kind of the same as rest of specs in that manner. So again, homogenization. No clue what the people who design and keep rogue around do, but for me it seems they plan on doing on specs the same. Maybe they lack ideas, I don't know.
Do you want an idea? Fully rework a spec, make it more demon-hunteresque. Or make it more medium ranged sort of, that change to have the regular melee attack turn to a shuriken toss when at range is a good idea. Or something. Just differentiate bigger between specs.
5. Passive damage. It's a big thing for rogues. Which is bad, because it means the difference between good rogues and bad rogues is small. And from some proposed suggestions for the next patch, it might be shrinking even more. People need to feel they are doing something and making themselves good. By having over 60% of their damage be white damage from melee and poisons it's just making it boring. In the end, what's the difference between someone who mashes buttons at random and a good rogue? 10%? too little.