If it's not that you can't do it, it's the fear of being greedy. Chances of making a big profit with a small investment are slim, while making a small profit with a big risk might not feel enough. I always tell my friends to first use paper money to understand the system's functions and operations if they don't know how to play, and only start with small investments once they are familiar. Making money is not difficult as long as you are patient. It makes sense to talk about this, but having discipline in investing is also important.