Didn't think my comment would cause so much debate.
Lol at the person who was claiming a 9-5 job is as risky as poker because you can made redundant at any time, what an absurd comment. There are no two ways around it, if I could have a 9-5 job making the same money as I do now, I know which one I would choose.
Poker is a skill game, but obviously there is a lot of short term luck/gamble. If we play enough hands, the variance will start to even out (although there is debate about whether it truly evens out). You should exercise proper bankroll management so that when you do hit a "down-swing" you can just move down the states where you will be less effected by the losses until you can rebuild and move back up.
As Castiel said, for everyone who wins there is 5 or more that lose, thankfully this number is closer to 20. I read once that only 5% of poker players are actually long term winners. If it was that easy, and everyone could make money doing it, then no-one could make money and it would be unsustainable.
What pains me to see when playing is the newcomers who think they can just pull up to the table and make a million over night, they're normally the people who end up going home with less (sometimes a lot less) than they came with, and they're what keeps the poker "economy" alive. If everyone was a tough regular player, the edge would be so low that only the very best could make a small amount of money, and anyone would be stupid to try and do this for a living.
It takes a lot of time and effort to be a good player, constant studying/learning is required or you will just get left behind and will not be able to compete at a high level.
I don't play much online anymore, just because its too damn tough. There are so many regulars at the stakes I want to play that it just becomes unprofitable and I don't want to pour my time into something where I'm not making considerable money. That's the reason I have shifted my focus to playing live since I turned 18, there are a lot more "fish" with more money to lose.