Learning from others mistakes it good. But how many people do it. Its rare that people learning from someone mistake. Everyone think that he knows everything and he is the expert when he or she make some profits. But but that over confident pull you down because for that confident you take wrong stape and for that wrong stape you lost your money because of that you must follow if you have someone experience who can give you advice. Or otherwise you are alone then learning don't try to be an expert at the beginning.
Making profits or winning has got a way of making you feel like you are just good enough and your decisions were just perfect and if you are not good enough to having self control, you may just jump into thinking that it's that easy and you can always continually win so no need of seeing what others are doing or even learning from their mistake.
You may at some point feel like you are not capable of making such a mistake so you just go ahead make your picks and stake without much consideration in to what the possible outcome could be because you may seem too sure of what your picks are. It's very important that at every point we should get to know what others are doing and also make sure to learn from their mistake so we don't fall victim of such thing happening to us aswell because we didn't take our time to observing and learning.