Why not you shouldn't see the amount you get you should see the return if you invest 0.003 bitcoin and get 0.0006 in few months the return is really less around 2$ but the percentage is 20% which means if you put 1000 you would get 200$ this percentage will surely encourage your mind to invest more next time
When you don't have a money $1000 to invest then better start with whatever you have first instead of waiting for accumulating $1000 because before reaching that $1000 accumulation you will gain an experience with small amount how these investments work. Once you start then you can add small amount whenever you got funds and can reach your $1000 or more.