Well, it's different thing now if luck is included.
I think that even you're not lucky but with some chance of working for strategy that someone knows, they can still win.
But if we'll be including luck, it's totally a different thing to talk about and there's no argument with that.
If it was possible that strategy generates constant income in gambling, I think lots of casinos would have closed their doors already. The whole point is that the casino has an edge and they do so in most cases. There are of course players that are more successful than others, but in aggregate I think there would be no strategy that everyone can equally apply and win.
And by the way if someone had such a strategy, I doubt that the person would be willing to share it publicly. It would make most sense for anyone to exploit it until the masses find out about it and exploit it to the extent that bookies could respond.
It would be only applicable if you do deal up with those games that which strategies are really that applicable like on sports betting or some card games on which you can be able to tell that you can make profits out of it if you do really know on how to beat up other people in terms of the games involved specially on poker on which it might sounds possible but actually true that there are ones who do make a living out of it but in speaking about casino games then it will really be that a different story on which this is why its important that you do really know on what you gonna deal up with and its important to have such realizations at least on how you do deal up with things accordingly. Strategies will really be that relevant into those games on which it will be having that kind of application or what type it would be.