The lesson we learn from trading experience and articles we read are quite different, though the lesson from both are very important in trading but the mistakes of some beginners, they get much confidence in trading after learning only from books.
Experience gives the best lessons to traders, which beginners should never be in haste or be so confidence to trade with big amount of money by only gaining knowledge from reading books about trading.
Trading is a very delicate activity that require adequate training and experience that is beyond knowledge gained from reading books alone. It's advisable to undergo adequate training before venturing into trading.