You can trade mutual funds in your roth ira and compound it tax free. upon 57 1/2 you can start taking money out - again tax free and meanwhile you can continue making money in some other endeavor. Most people have a business or a profession (lawyer, pilot,doctor) that best be utilized still rather than trade full time. I know many dream of trading full time and be the next George Soros but how realistic is that? Sector funds and index funds eliminate the idiot fund manager error and the need for the art of stock picking.