I would add regarding new traders is that its not so much that their ideas suck but that they run out of capital ie blowout. I wonder how many people over the years have blown out, I know some good traders that blew out. Its not always because they are unskilled, sometimes "shit happens" and great traders get caught, 2008, 1998, 1987 etc. Again regarding execution if you go all in you better be right, so one should think hard and long about position size in an account.
