Thats it This is enough for me
That's what I do too. But I don't wait for my balance to be doubled sometimes 5-20% profit is already enough for me. And that's the right time I'm withdrawing my balance. I'm not greedy anymore because I want it to be in the right way of putting my bitcoins at the safe place and don't wanted to use it for sometime.
I agree, too many people are greedy when it comes to gambling and I mostly see it when they are on a roll and they think they can win even more and most times then not they lose it all. That is why when I gamble I'm happy with 2x and just stop, I have tried for more on occasions and have got lucky but it doesn't happen too often so I stop at 2x.