Ok, why this or that RTS game isn't a 4X.
Exploring. In Warcraft, this amounts to lifting the fog of war, seconds of the game. You have to be aware of incoming attacks, but that's not exploration, just scouting. A recon screen in front of your combat lines is hardly cause for saying you continue exploring throughout the game. This holds true for most of the other RTS games people have mentioned. Scouting plays a dominant role in keeping tabs on your opponent, exploring is a trivial process, something that's done the same way every time and has little bearing, if any. Exploration in the typical RTS game is one dimensional, find the enemy base. Calling Warcraft an exploration game is almost as bad as saying it's packing material because it comes in a cardboard box. Unfortunately, you still explore.
Expanding, the kicker for most. What is expansion in the typical RTS game? You start with a command center type structure, and build up around it. Some very large
scale games like supreme commander actually make it reasonable to set up satellite installations, refueling bases, a rolling front line of infrastructure taken all the way to the enemy base. Others like Kohan are even more expansion based, it's entirely 4X style in how expansion is done. If the RTS game is most efficiently played with a single base of operations, it has no expansion at all, and is thus NOT a 4X in any way, shape or form. This kills 90% of them, due to shitty implementation that creates severely damaging results when you encounter the enemy force with a portion of yours. You get raped, and do minuscule damage, and the rest of your army then gets raped too. The opposing side is a game like Civ, where an army attacking is going to lose comparable forces regardless of how much bigger it is. You could bring a billion warriors and you're still equally fucked by a single defender, he's going to kill that first guy and maybe a second. Having three attackers would have been much more effective.
Exploit. Most RTS games have this one down pretty good. They generally have less complex methods of exploiting them, horrifying ones like the warcraft games worker lines or automated resources are the most common type. Some RTS games even have more complex systems, such as Rise of Legends with the neutral points of varying types that you capture for different bonuses and resource incomes, and the expanding cities that you improve to boost your limitations. Generally speaking, any RTS fits the 4X definition on exploitation.
Exterminate. A real no brainer here, I think this one is obvious enough that no one needs it explained.
The definition of a 4X game has nothing at all to do with a culture victory, or an ultimate research goal. It's exactly what it stands for, explore, expand, exploit, exterminate. Most RTS games lack the first two almost entirely, exploration being a token process, and expansion being counterproductive. When you combine them into the full definition, very few RTS games actually follow any of it. They are not four separate sections, but a process. You explore your surroundings, expand outward, exploit the resources you're taking into your empire, and exterminate the enemy. This kinda negates the whole alternative victory condition if you stick to the original meaning, diplomatic, cultural, research, all that stuff is counter to the original definition.
Warcraft is not a 4X game because expansion is a no no, and exploiting comes independent of the limited expansion that is possible. Rise of Legends is a 4X game, by definition. You explore(a severely limited process yes, but relevant to the expansion, not just to find the enemy base), expand into the neutral sites, exploit their resources, and exterminate the enemy with them. Is it the same style of game as MOO? No. MOO was a large scale, turn based space 4X with stack combat and an emphasis on research, Rise of Legends is a fast paced RTS with realistic tactical combat and a comparatively minuscule research factor. They are both 4X, it's no more arguable than saying Australia isn't a continent because it's smaller than all the rest. When something is defined as such, it is. Being arbitrary is the nature of a definition.
Sins is a 4X, you explore your surroundings, expand outward, exploit the resources, and exterminate the enemy. Rather straight forward and unambiguous. Sins is also an RTS, as the definition of RTS applies to any and all real time strategy games, regardless of whether they fit into the definition of 4X as well. Legions of Iron fits the 4X genre like a glove as well, if with a horrifyingly bad game play. Homeworld doesn't, no expansion. There are many games labeled as RTS that are 4X, not many of them are space games, and I haven't played any with the scale of Sins that were even marginally good, but there are a lot of them.
Quicky multi-player people, STFU.
Even on your 10 planet map, you're still playing a 4X even when it doesn't feel like MOO and has no depth outside of combat. That the asinine comments don't apply to a game of size and are thus irrelevant even if they were to define the game as a 4X is added reason to give it a rest.
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appears to me as a too generous gesture : 
Even on your 10 planet map, you're still playing a 4X even when it doesn't feel like MOO and has no depth outside of combat. That the asinine comments don't apply to a game of size and are thus irrelevant even if they were to define the game as a 4X is added reason to give it a rest.
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