True. Doubting yourself and being too full of yourself can both wreak havoc on trading profits. I’ve experienced both. At first I was overly anxious and headstand, which caused me to lose out on a lot. Once I got better at trading I got a little too comfortable risking too much and lost a good bit, which was enough to humble me. I think the best traders find the balance between the two.
Over confidence in case of trading activity can lead to unpleasant consequences. For example, if you see that everything is okay you start to open positions chaotically and turn off your brain and logic. Everything because you think that you have started to feel the market and you can do everything and will be profitable. Nevertheless it's not like that and often such behvaior on the market leads to blowin of accounts. Be careful with this thing.
Overconfidence can lead a trader to make decisions that are careless, impulsive, and rash. These types of decisions can lead to the loss of money in trading; this is especially true in the Forex market because of its high volume and volatility. So, a trader should be careful to maintain control over emotions and let logic rule the actions rather than overconfidence.