I hate the way EA games nag me to death about online "features" that are really just a poor excuse for DRM and spam.
1. Click something in a brand-new game I'm excited to play.
2. *pop-up* Welcome to EA Spam-zone! To get started you'll need an account, give me your email so I can spam you about some DLC and games you don't care about!
3. *exit out of pop-up* You chose not to create a spam account at this time, so we assume you are a nasty pirate and have disabled half the features of the game you just bought.
4. *30 seconds later, loading into the game for the first time* Hey did you know you can sign-up for some new EA spam attacks?! Sign-up now to enable playing the game you bought.
etc
Not all EA games are this bad, but lots are e.g. recent Need For Speed.
So that's my reason, is that dealing with EA in recent years involves so much advertising and DRM crap that I feel like I am going to ghetto websites to play flash games. Add this to the general list of atrocities like destroying formerly good game series in the name of selling out, horrible start-up videos that they try to stop us from disabling, etc.
The thing about Steam is that I don't particularly like any of valve's games. Half-life, TF2, Portal, all lose my interest in less than one hour. But Valve did not create steam to push their own games down my throat, like the reason EA made origin. Valve set out to make a games distribution platform, not to give themselves tighter control over the customers of their games.
What would it take for me to use origin? EA would need to lose billions of dollars for multiple years in a row, fire their board of directors, and replace them all with human beings that have decent souls.