using huge amount of capital as a newbie in trading can lead to a careless trading decision as you have too much to throw around until you lose everything then start all over again.
This does not need to be a common scenario for all the traders; if you value your capital then you will not go for random trades. So, huge capital got nothing to do with your losses but only your negligence of technical part of trading. We must give more importance for technical analysis in trading so that we could make profits on regular basis. People who are carelessly making trades may make profits one or two days and then may loss due to the reason of luck not in their side.
Master yourself first (emotions, patience, risk appetite etc) before you master your trade.
Yeah, self-control is more aspect of trading but only after big losses, traders start realizing it. When getting into trading, we need to prepare ourselves for lots of things and self realizing must be one of them.