The problem is exacerbated in this current expansion because for mages, capping hit has become a much more difficult proposition. A lot of things are working against us, and the issues don't seem to be going away as our gear improves.
Let's indulge in a quick rundown of how the stat works, to provide context. If you've been playing a mage for a million years and already know absolutely everything, feel free to skip the next two paragraphs.
Hit rating, hit chance, and the hit cap
Hit rating is a stats that improves your chance to hit an enemy with your spells. Your chance to hit a mob depends on three things: your level, your target's level, and your hit rating. At level 85, missing with your spells is usually not an issue until you start going into raids, where by default, the bosses are three levels higher than you. At that point, without any extra hit rating, your mage has an 83% chance to hit a raid boss. That means every time you cast a spell, you have a 17% chance to completely miss with it.
It takes 102.45 points of hit rating to increase your chance to hit by 1% at level 85. So to reduce your chance of missing to zero, you need precisely 1,742 points of hit rating from gear and other outside sources -- no more, no less. That 17% hit chance or 1,742 points of hit rating is what's considered the "hit cap." Until you reach it, you can still miss, but if you're at the hit cap, any extra hit rating is completely wasted.
Those numbers again: 1,742 hit rating, which equals 17% hit chance.
How important is it to cap your hit?
There has been some debate this expansion, even among hardcore raiding mages, about whether or not capping hit is still a priority over intellect, a stat that is so incredibly sexy to mages in Cataclysm it's almost ridiculous. With so much hit being required for the cap and intellect being so amazing, is there a point at which a raiding mage can say, "You know what? I don't care if I still have a 2% chance to miss the boss -- I'm taking that trinket with the 300 intellect."
It's a valid argument, but ultimately a wrong one. I will say this once, and only once. It has always been true and will continue to be true as long as Blizzard uses its current statistical design. So pay attention, because I only have room left for a few hundred more words, and I don't want to have to repeat myself:
You still need to cap hit.
The complicated math is there to back this up, but the concept is pretty simple: You do zero damage when you miss. In fact, when you factor in the time you spent casting the spell and the mana you wasted on the miss, I'd say you're actually doing negative damage. If you are missing even 1% of the time, you're reducing the value of every other stat you have, especially intellect.
Now, should you be giving up intellect to cap hit when other stats are an option? No. But when push comes to shove and you are forced to choose between that awesome intellect trinket and the one that caps your hit, until other options present themselves, you need to suck it up and choose the hit trinket.
You see, mages truly have an uphill battle to fight here.
The problems with reaching the hit cap
Aside from the staggeringly high amount of hit rating you need to cap hit, mages also have a unique issue to contend with. Unlike most other DPS classes, mages have no talent that increases their hit chance. As an example, shadow priests have Twisted Faith, which for two talent points grants them hit rating equal to 100% of their spirit. Mages have no such talent. Granted, spirit is not a stat we benefit from in any other way, so a spirit-to-hit conversion talent wouldn't really help us, other than opening up additional gear options.
Still, the fact of the matter is that not having a hit talent means we have to scrabble together all 1,742 points of hit rating from gear, buffs, and gems/enchants.
How hard is it to get that amount of hit rating? Well, let's look at the current tier of gear. In a full set of tier 11 gear and a selection of item level 359 gear that has hit rating on it filling in the gaps, here's the amount of hit rating I come up with before enchants/gems/reforging:
That's with a hit rating-only filter on my item level 359 gear, a pair of hit trinkets, and a dagger/off-hand frill combination that also has hit on it. To cap that, you're going to have to come up with 474 points of hit rating from gems, enchants, buffs, outside buffs, and reforging. So with very carefully prioritizing hit on all my gear choices, I come up with a significant amount of extra hit that I still need to sacrifice other stats in order to obtain. It's not impossible by any means -- just difficult.
And it doesn't really get much better as gear improves. The number I come up with prioritizing my gear choices for hit in the Tier 12/Firelands gear? 1,235. Keep in mind that the stats on this gear are subject to change; more gear may very well be incoming on the PTR before things go live, and know that there is no item level 378 hit trinket option available, so you might very well still be using a lower-level option that helps you with that initial hit number.
The bottom line
To get your hit capped, even at very high levels of gear, you will need to sacrifice other stats. It's designed to be a trade-off, and for mages, it absolutely is one. In the past, mages didn't need to worry too much about capping their hit, since at high gear levels, your hit from gear pretty much covered it and then some.
These days, though, reaching the hit cap has to be a constant, conscious decision. If you're planning to raid, you simply can't just blindly equip every new upgrade you come across. You have to take into account its effect on your hit situation and then calculate its value after reforging.
The strategy for capping is pretty straightforward. First, pick your least attractive secondary stat. Depending on your spec, this will either be haste or crit. Reforge that into hit on every piece of gear you have. Once you've done this, it's time to make up the difference through enchants and gems. If you still fall short, keep in mind that you can also glean a bit of hit from consumable items
and outside buffs, like Heroic Presence if you're lucky enough to have a draenei in the raid.
Edit: I am Horde, and don't play with Draenei. Also, I don't read tooltips very well, apparently. None of which excuses that I am painfully, blatantly wrong in suggesting that Heroic Presence still applies to anybody other than the Draenei in question. As always, I blame warlocks.
Hit is still the priority for mages. Once hit is capped, you can absolutely stack other stats. It's a difficult road right now, but doable. Make the effort. No single stat increases your DPS in raids faster than hit rating until capped. Not even intellect.
The good news, though, is that the hit rating required to kill warlocks is still zero. So get on that.
Every week, Arcane Brilliance teleports you inside the wonderful world of mages and then hurls a Fireball in your face. Start off with our Cataclysm 101 guide for new mages, then find out which spec is best for raiding, get advice from the poor mage's guide to enchants, and learn how to keep yourself alive.