Greed is the major reason why newbies lose money in trading and if the professional are finding difficult to make 12% in a year what make you think you will be able to make 100% a month as a newbies.
Greed is something that will never make you decision on the right time. a greedy person thinks that the price will fall more and then he will buy some and miss the chance and when want to sell his coins again he looks for the price to grow more and more and suddenly the price drops again and doesnt make any profit. Thats why it is said that greed is a curse.