I do not care for companions. Which makes it all the more galling that a glut of new – and desirable – games all but force them upon you.
Take Star Wars: The Old Republic. At the conclusion of your introductory zone quests, your first companion joins you on your journey to right wrongs and establish peace throughout the galaxy (or wrong rights and establish dominance, as the case may be). You can, to be sure, dismiss this companion immediately. However, the game is balanced under the assumption that you have a companion aiding you in each encounter.
In addition to SWTOR, Diablo III also utilizes a companion system, although, at least in the Beta, you certainly don’t need your companion in order to accomplish anything. And I believe the same goes in Skyrim – companions are available, but for the most part unnecessary.
Regardless, the very existence of a companion system gets under my skin. First, for roleplaying reasons (that’s right: roleplaying). I like to consider my characters to be mighty heroes, lone bastions of justice holding back a tide of darkness threatening to flood the land (I have a good imagination). The thought that I would want, much less need, a sidekick infuriates me. How powerful can I be if I require the help of some Robin to my Batman? Doesn’t that mean I’m not Batman at all?
As a brief aside, multiplayer is a completely different animal, as are group quests, dungeons, raids, and the like you run into in any MMO. In these situations, my companions are my comrades in omnipotence, banding together to fight creatures that are, uh, more omnipotent than we are.
Now, for the technical reasons. Frankly, if a game is balanced to require a companion, you would think it could be balanced to not require one. My suspicion, however, is that companions exist in order to make up for the deficiencies endemic to any class archetype.
For example, take your standard tanking class. Generically, tanks are long in defense and short – very short – in offense. Therefore, you gift a tank with a friendly damage dealing companion, and suddenly all is right with the world. Or vise versa with your DPS class – grant them a meat shield and send them on their merry way.
If that’s the case, then I call it laziness – which would be inexcusable. However, I’m willing to bet it’s a combination of several factors. I’m guessing not everyone has such a stalwart anti-companion point of view, and, in fact, that most folks are ambivalent, while there are more companion lovers than haters. That fact, taken in concert with easing the burden of solo play balance, is what stuffs us with companions.
As for me? My companions will be taking their ease on board my starship, or in the New Tristram town square, or in whatever tavern they choose in Skyrim. Essentially, anywhere except with me.