Hi all. This is my first post. There seems to be a fair amount of evidence that intraday stock prices move (mostly) randomly on short time scales. My question then is what if you were a day trader and you randomly picked a buy point, and then a sell point every day, for a given stock. What would your long term average be (ignoring commissions) after many years? If stock prices move randomly, it would seem that you would win and lose about the same amount on average, except for the long term trend in the stock price. Therefore, it seems like this strategy would simply follow the long term price movement of the stock. However, I also read that most day traders LOSE money. Does that mean that most day traders do WORSE than random? That is, they are actually surprisingly skilled at doing poorly. If this is true, why? Seems like it can't just be the commissions, which I ignored above. Would be curious to hear your thoughts on any of the above. Thanks.