I'll preface this by saying that I don't have Origin. I've managed to avoid it thus far. Very sadly I'll probably lose that battle one day when I finally decide to play Mass Effect 3.
I'm surprised that some of these points regarding Origin haven't been made. I'll skip the ones that already have, since most of them are valid.
Origin wasn't created in the same spirit or intention that Steam was. Steam was originally a digital distribution tool for Valve to use for its own games for patching and downloading updates. Over time, they gradually added more multiplayer community support (which pissed a lot of people off at the time, since they cannibalized existing communities) and then they started adding more 3rd party games. Eventually it morphed into a full-blown digital distribution network that we know (and some of us love).
Origin wasn't created this way. And I think it's one of the main reasons everyone hates it.
EA sold games through Steam. EA's games sold through Steam quite well. Nobody to my knowledge had any issues with EA's games on Steam. I have many EA games through Steam myself, including Mass Effect 1 & 2, and Dragon Age 1 & 2.
Then EA decided that instead of distributing its games on Steam, it would make it's OWN digitial distribution system for its own games, like Valve had done. Steam was becoming too bargain-bin for EA. Steam Sales were incredibly popular, and I don't think EA wanted to play ball. EA didn't want to put Mass Effect on sale for $10, just so that it could compete with other "on sale" games. It wants you to pay $20 for Mass Effect. On Origin, EA wouldn't have to compete with game sales, and could keep the prices on its games as high as it wants. Go and look at the prices for EA's games on Origin and compare them with the sale prices you can get on Steam for other AAA titles, and I think you'll agree that EA prices its titles higher.
To add insult to injury, EA decided to then not offer any of its games through Steam anymore. This angered the game community. Everyone REALLY wanted to play Mass Effect 3. But we already had Mass Effect 1 and 2 on Steam, and we want to buy the 3rd on there too. Gamers don't want to be FORCED to use a game community just to play a game that they want to buy. Suddenly gamers who were used to Steam were forced to install Origin on their system to play the games they wanted to play.
Now to be fair, Steam does this too. There was quite a bit of griping a few years back that you would buy a DVD game in the store off the shelf, but then when you got it home, you had to install Steam and register the game on Steam in order to play. Origin just pissed us off more because we were USED to using Steam and had grown to like it, and we knew that there was really no good reason why we COULDN'T use Steam. It's just that EA didn't want us to.
EA could have built Origin and released Mass Effect 3 on both Steam AND on Origin. But instead they're essentially milking the game community. They're forcing the game community to help them build their Origin system, and they have the ability to manipulate us into doing this, because in the end the game community just wants to play Mass Effect 3, dammit. It's like always-on DRM, like SimCity. Gamers will ***** about it on forums forever, but in the end we just want to play the game.
We'll grumble about it until the end of the Earth, but in the end, we'll jump through whatever hoop EA wants us to jump through to play the games we want to play, and EA KNOWS THIS.
EA knows it can basically tell us to "Jump", and we'll grudgingly say "How high?" as long as after we're done we can play Mass Effect 3.
That's what I hate about Origin at least, and that's why I'm glad I'm not using it... yet.