1. deathgrip
2. The customer service is in need of brain surgery half the time. It took me sending my product code twice for those robots to pick up on it.
This. And
3. Offline mode works fine for about three weeks, but after that Steam seems to
must phone home, or die. If you are not on the Internet when Steam feels this urge, then you will not be allowed to play the game you paid for. Which might be allright, if you were told up front, that such is the deal. But you are not, instead you are told that you only have to connect once to register and unlock your game, and from then on you will never ever again be compelled to use Steam. Which is not true: If Steam has not phoned home after three weeks it gets nervous, refuses to open your games and tells you that it wants to phone home for an update.
I know a guy, who is in Afghanistan right now, Internet is crappy there, so he cannot always access his Steam only games. I know another guy, working in the Balkans, where Internet also is not always up to American standards, he likewise cannot access his Steam only games. And then I know me, who wanted to have another go at Empire Total War the other day, but because I had forgot to pay for my internet account, I was not allowed to play the game I already paid for, Steam refused to start. And as ETW is Steam only, well...
Ok, most people have good connections and are online 24/7, to them Steam is no problem. And because it works seamlessly for them, some of those people somehow believe that all who complain about Steam must be stupid. They are like Marie Antoinette, who didn't understand all the fuzz about people starving because they could not afford to buy bread: Why don't they just eat cake?
Luckily we have indie games. I can heartily recommmend AIWar Fleet Command and, of course, Dwarven Fortress.