trading psychology is a big factor, people tend to do some risky things in demo coz the money aint real and the fear of losing is not there, another thing i guess the demo is quiet different from live, in terms of execution, and slippage, and other things that the crazy live environment has to offer, lol. but demo has its uses, i still trade my hotforex demo account. at times i trade it just for the sake or releasing some stress.